The Bulletin – March 1980

THE BULLETIN

Journal of the Association for Petroleum and Explosives Administration

March 1980

Contents

Talking Point

Notes & News

Explosion et Fire Hazard of LPG

London News

Fatality from Petrol Appeals

Bulletin

Published by the Association for Petroleum and Explosives Administration

73 74 75 90 91 92

A.G.M. 95 Proceedings 99

Baseefa 100

Honorary Secretary

Mr. E. Brown

Cambridgeshire County Council

Opinions

expressed in this Journal are not necessarily the views of the Association

Talking Point

Vii th a new decade upon us I look back over the "past ten years at the way we have been affected. I find that change in areas of responsibility, changes in legislation, together with new ideas and gadgets, increasing use of electronic equipment were constantly thrust upon us and we reacted accordingly. This is where the Association has helped in providing a platform for discussion in these areas.

As we oroceed into the eighties the • . . h· role Association is continu1ng 1n t 1S with a seminar planned on Conveyance 1n June for which details are inside the Bulletin. I feel this augurs well for the future.

Honorary Edi tor Mr. J.A.J. Thompson,

'!bank you

'lb.e recruitment campaign launched in the last Bulletin has produced some results; application forms are still available from the Hon. Secretary. I would again ask that each member enrols at least one new member this year.

New Uembers '!be Association welcomes the following new members

Mr J. G. BI eke

Mr. K. Coney

Mr. G. Coulson

Mr. Galbrai th

Associate Member Associate Uember Murco Petroleum Edinburgh

Mr. Caruth Co Down

Mr. P. Newton Co Antrim

Mr. Hanna Co Down

Mr. Agnew Co Antrim

Mr. Wright Cambridge CC

Mr. Wilson Co Antrim

Mr. Chesworth Beds CC

Mr. Fryer Highland Regional Council

Mr. Mc Bride Forth Ports Authori ty

Mr. D. Humphrey-Woodward Kent CC

Mr. Geary Vauxhall Motors Ltd.

Mr. Batram

Mr. Kennedy

Mr. T.J. Wilson

Mr. R. J. U!aman

Mr. M.R. Thompson

Mr. 1:". r.eynor

Mr. D.J. Green

Kent CC Associate Member Co Antrim Guernsey Co Down Co Down Gloucestershire CC I.C.I.

At recent meetings the following have been appointed Branch Secretaries.

Midlands Branch

N. Fox 8, Fordham Avenue, Stratford Upon Avon Warwicks

South Eastern Branch

J. Ellis 127, Epsom Road, Guildford Surrey.

PETROLEUM 80

Your Association has arranged a Seminar on the Conveyance of Hazardous Substances to be held in Cambridge on 19th June, 1980.

This Seminar is to be opened by the Chairman of the Health and Safety Commission, Mr. Simpson. There will also be a representative speaker from the Health and Safety Executive, the Local Authority and a Petroleum Company.

'lb.e theme of the Seminar will be conveyance as seen by the speakers with the emphasis on the future. There will be ample time allocated for questions and discussion.

Full details and application form will be sent to each member of the Association and other interested persons. Further application forms may be obtained from the Hon. Secretary, Eric Brown.

It is expected that this Seminar will be well supported by those interested in conveyance and it is suggested that early application should be made.

The AGM

The AGU is to be held at the West Uidlands Fire Service HQ on Wednesday 23 April 1980 in Birmingham. It is hoped that as many as possible will attend the meeting. The speaker in the afternoon will be J .M. Adams Deputy Oirector of Baseefa who will talk on the work of that department.

Subscription Charges

The Council has found it necessary to increase rates by £1 due to increased costs mainly in printing and postage rates. The rates have not been increased since 1977 and it is felt still provides good value.

The Treasurer has asked me to remind members that prompt payment of subscriptions help keep costs down.

OF LIQUEFIED PETROLEUM GAS

By D.J. Rasbash Department of Fire Safety Engineering University of Edinburgh

Introduction

Liquefied petroleum gas contains two main constituents, butane and gropane. Commercial butane and propane boil respectively at about -2 and -45 C. 'For the most part, the material is transported and stored at room temperature in .the form of pr3ssurised liquids, the pressure at the highest expected ambient temperature. of 60 C being about 7 bars for butane and 22 bars for propane. However, quantities in of one thousand tons tend to be stored as a refrigerated liquid at or near the boiling point. Ships' cargoes may be cl ther pressurised liquids or refrigerated liquids. In addition, in parts of LPG installations the liquid is Vaporised and is transported as a gas either by itself or occasionally as a mixture with some air.

General Fire and Explosion Properties of LPG

For the most part, the fire and explosion properties of LPG do not become manifest until the liquid is vaporised in the presence of air. However, the possibility of pressure bursts in the pressurised vessel is also a hazard, particularly in the presence of heating or fire, and this will of course produce physical explosive effects. In a manner similar to other flammable gases or vapours, the gas will not propagate flame outside certain limits of concentration which for propane is about 2.2 10 per cent and for butane 1.8 -9 per cent. The max:Lmum explosive pressures occur when the concentration is about twice the lower limit value. Concentrations of flammable vapour and air within these limits may be ignited by a small source of ignition such as a small flame or a spark with an energy as low as 0.3 mJ. <Altside these limits of concentration. not even a large flame would be able to produce flame propagation substantially beyond the driving influence of the flame. At any interface with air on one side and a flammable vapour abOVe the flammable limit on the other, including particularly the neat vapour, there; will be a zone within the limi. ts which can be ignited and produce; a t leum continUing fire until the vapour has bw:ned away. Refrigerated pe ro gas in a vessel may be ignited in the same way as petrol and will bu%1l in a1 tent sim1lax" manner in that the flames above the liquid surface will supply the a heat of vaporisation of the vapour being fed into the flame.

Any Spillage of liquid from a pressurised container will result in total dispersion and evaporation. In general, a small spillage of liquefied gas will also vaporise quickly. If large quantities of et.ion LP(; ax"e spilled then the surrounding area will be rapidly cooled and vapor sa rt ronan a es will be greatly reduced. HoweVer, if spillage takes place 0 d will ted area in deep water, the vaporisation rate will be much highera:. it is end to continue unabated. :r am not aware of any measurement of this r fO; tNG somewhat less if20f the same order for liquid propane as it is , Ch is about 0.18 kg/m s.

If 1 in an enelosed a Pocket of flanmable vapour air mixture builds up, particular y sure then the propagation of flame through the mixture can give rise to pres effect I 1 cubical in sha s. f the mixture is completely enclosed and is approJ\-W.1Q e Y 7 ha gauPe , .then the maxiJm,.un pressure that may be developed is of the order of re t gee If a flammable vapour air mixture is established in a long duct, then a 1'YPe of explosion Jalown as detonation may occur which might give pressure effects ocally well in excess of 7 bars. Buildings m y be severely damaged at intexnal pressures in excess of about 0.1 bar and i t be remeJDbered that for a complete enclosure the pressure that builds up is approximately proportional to the size of the pocket occupied by the flammable gas air mixture in it. Thus for a

volume of, say, lOm x lOm x 4m (i.e. 400 cubic metres) a pocket of flammable vapour air mixture only one-seventieth the total volume, i.e. a volume of 6 cubic metres, can, if ignited, give rise to major damaging effects. To fill such a volume with the stoichiometric mixture, which is the most explosive within the flammable range, would require about 50g of either propane of butane vapour. Thus a small leak can go quite far in producing damaging effectso In practice windows and doors that may be present in most spaces could provide some relief. These would burst open, limiting the damage.. The violence of the explosion would depend on the configuration of the items in the space through which flame is propagating since the flame is accelerated by turbulence.

A major difference between petroleum gas and natural gas or town gas is that it is heavier than air. This increases the risk in a number of ways. Thus there tends to be more ignition sources in the lower parts of a room than in the upper " partP. Also LPG appliances tend to be in the lower parts of working or living areas and leakage falling from the appliance itself does not have much opportunity to become diluted to safe belc:>w the low:r en the other hand, leakage rising from natural gas for a substantial distance prior to reaching a ceiling. There also tend to be more POCkets, recesses and inaccessible spaces near the floor or the ground where flammable vapo!.lrs might accumulate. Finally, when ignition does take place, there are mor obst"acles in the path of the flame near the grc:>und than :mder a ceiling, causinge the flame to become accelerated and the more

f1ajor Fire and Explosion Hazards Associated with LPG

Thepbove gives a summary of the normal fire and aSsociated with LPG. However, experiences over recent hav7 that certain major and even disastrous may this due to the ability of large of the gas 0to flash into the Va form. There are two major types of hazard whether ignition takes Pour place soon after spillage or there is a substantial gap. If the vapour ignited soon after the spillage has taken plac7, a is produced are consumes the vapours very quickly; far more than 0they were bumin s a liquid over the initial surface. This Figs 1 and 2 go S a how (::.) 40cc liquid propane gas burning from a cylinder 2.5 cm diamete which 0 0 f ill f th r, and (b) the flame that formed vapours rom a sp age 0 e same amount liquid propane under water are ignited. In the fo:me r case the fire takes of ....; ..,utes. to burn out: in the latter case the fuel consumed in two three 11...- 0 fl seconds Howevel:', it can be even more dangerous the anunable gases evolved f •. flashing of spilled LPG are not ignited.. They may then be Carried by :: the 0 own flow or by outside wind to an area where they can produce much er theJ.r o "t d age when e •

Table 1 gives some information of these hazards. There is a SUIrinary f th maxirnUID size of fireball that may be obtained from the rapid sPillage°and e isation of different quantities of LPG. Also given is the distance at wh.i vaporcellulosic material may become ignited by pilot flame when under the inn ch a heat radiated by the fireball and also the distance at which a person of of the body exposed to the radiation of the fireball might feel unbear:l Parts It should be stated that for ignition of materials inside domestic pr 0 e Pain. distance for pilot ignition will usually be about 0.6 times smaller the shown in Table 1 since windows will absorb two thirds of the radiatioo Alose spontaneous ignition may be a more appropriate criterion for fire th • il so ignitiOl'l in this situation. In addition, normal vegetation Would much moisture to be ignited at the distances shown. HOI.ITever, it Woulda: . t d that dry vegetation and thin cellulosic materials would be subject to pOl t expec e th di t o °ti 0 ignition up to e stance sated, the on sources for the latter bein fires started by spontaneous ignition nearer to the fireball. Humidity in J!e atmosphere and rain would reduce considerably the extent of fire spread. Table 1 alsO gives estimates of the maximum distance that flammable vapours may be carried

and still be dangerous at points downstream of spUlages and the maximum area of a flashing fire that might occur when such spillage vapours are ignited when carried downwind.

It should be emphasised that the figures given are based on very meagre experimental work and an incomplete understanding of the processes involved. However, the table does give an indication of the dimension of disaster that might result from a spillage of even moderate quantities of these liquid gases. Thus a 20-ton spillage from a road tanker could produce a flash fire over 5 hectares (about 10 acres) with transient flashes up to about 0.9 )an and a 2,000 ton spillage and vaporisatiqn might produce a fire of 2 square kilometres with transient flames reaching a distance downwind of 8 kilometres from the point of spillage. These areas would contain a substantial fraction above the stoichiometric or even the upper limit concentration and could burn for tens of seconds in a given locality.

In order to produce the effects outlined in Table 1, not only does the spillage of the liquid have to take place but also it must be vaporised or dispersed in a relatively short time. An estimate of this time for the condition of rapid ignition is given in the table and it will be seen that it varies from 1.5 minutes for 2 tons to 13 minutes for 2,000 tons. To produce the maxirrurn diameter fireball under conditions of rapid ignition the time of release and dispersion need to be less than about twice the time of burning of the fireball. The latter is shown as varying from 4 - 22.5 seconds over the range of spillage sizes in Table 1.

The question which arises is, how possible is it for spillages with these characteristics to occur? Experience has shown that for LPG kept under pressure in a storage vessel it is possible for the vessel to become ruptured and to disgorge all its contents in a very short time. Moreover, the bulk of 1 ts contents when disgorged ",ill almost immediately be either flashed into vapour in the atmosphere or dispersed as a fine mist which is just as dangerous. The most common way this occurs is a result of a fire, possibly due to a leak, which the storage vessel and heats it, thus weakening the steel. Occasionally however bursts have occurred, either because of local damage to the storage vessel or expansion of the liquid following over-filling.

The mechanisms of spillage with pressure vessels are much less likely with refri.gerated liquids. The latter are stored in insulated vessels which are ITIlch weaker than pressure vessels, in fact not very dissimilar to ordinary tanks for large .scale storage of liquid. It is rare, but certainly e.. metallurgl.cal failure condition might occur in a tank, causUlg l.t to its contents. It is POSsible also under certain processes or . for substantial pressures to build up within a refrigerated • The rnal.n process condition is known "11 " and is due to the. variati· du t as ro over t on l.n pro c present in a tank Th h i 1 volatile produc may be allowed to flow above a lighter· morus a l er, dueStS A sinking of the Upper 1 . t th 1 ' e vo a e pro c. the ayer l.n 0 e ower one can cause . f vapour from lower layers which might overcome the eVolutl.on 0 el An accidental condition wh1ch might give rise to a Simile an bUrst the vessf bulk of the conten1:s of a tank and which is liable to would follow the puncture of a tank under the waterline th P tranding collision or some other mechanism. It is then POsslblel.f er through s ter the'cargo space. vlater being warmer than the cargo, PartiCU1';1 or to. en d ropane , can cause a rapid Vaporisation could split the l.t 1s amPaware, this has never happened in practice, nor has any As far as rl.'ed aut to define th . which . t . 1 "-01' work been car e conditions under l. ml.ght OCCUr but .. cannot be dismissede Refrigerated gas tankers might 1 the and metallurgical failure. a so experl.ence ro

If a spillage it still needs to be v· i ient rapidity. This is less likely on land for the reasonsap?rl.s ed with sea there 1s a continuing supply of heat from the water to thgl.ven abov7e en ie ing fluid since e spreadJ.ng vapor s

the cooling of the water below the spreading vaporising liquid will cause the water to sink and be replaced by warmer water from underneath. Thus the possibility of a catastrophe of dimensions that are indicated in Table 1 following an accident involving one or possible two liquid flammable gas tanks in a ship, is a very real one. However, the production of a of the above size is on the limit of credibility unless the tank concerned 1S already surrounded by a substantial fire Which would act as a dispersive and vaporising agent to the contents if these are released with sufficient rapidity by disl:Uption of the tank. A well known anal090us situation is the boil-over which may be caused when the hot zone formed in a tank of burning heavy fuel oil reaches a layer of wate.J:' that may be present at the floor of the tank. For a 20,000 ton gas tanker the involvement of all the tanks in one fireball situation can probably be l:Uled out. Even the extended unignited spill hazard is very unlikely since there will need to be a mechanism present which gives rise to the disgorgement of the contents within a number of different tankers in the limited time available. \"li th ING a mechanism has been suggested that local leakages and vaporisation of LNG within the cargo space even of LNG spilled at a terminal might stress the metal of the hull by cooling, which could then fail to support all of the other tanks. I am not aware of any calaxlation which shows this can happen in the necessary time to produce effects as in Table 1. This mechanism however, would not apply to LPG. en the other hand a single land based refrigerated tank could, if it collapsed, give rise to the disaster condition approaching those outlined in Table 1 if there \'/ere no I!vailable mechanism of channelling or otheJ:Wise controlling the released spillage.

there are two further factors which might make the sitUation even worse than -is apparent in Table 1. First, under some conditions explosion effects over a large area have been experienced following a greater than, say, some tens of tons of liquefied flammable gas in the open, even l.f the ignition source is a small one. This phenomenon is perhaps most likely when ignition is delayed but cannot be ruled out for immediate ignition with release from pressurised vessels. We still know very little about this phenomenon but I believe that it is more likely where pockets of flarmtable vapour air mixture may be a.llowed to accumulate in enclosed spaces and where obstacles, plant or buildings are present within the flammable vapour cloud which can increl!se the rate of flame spread by turbulence and pO$sibly local detonation. There is much discussion and some work proceeding on this topic but as far as I am aware, it has not been possible to reproduce yet the deVelopment of substantial pressures in the open under experimental c:ond1tions. If such pressure effects were, for example, manifested over a 1 -2 km 2 area over which a flashover has taken place following a 2,000 ton· spillage, then certainly \'lindows within the flash fire area and substantially beyond it would break and much damage would be caused to buildings within the area. This would allow the flames to ignite easily combustible material within the thus one might expect in a bui1t up area i terns such as curtains and foam fw:n1 ture and bedding would be universally ignited in most rooms. The breakage of the windO\"s beyond the initial burning area would assist in developing fire in this area by radiation. For this reason the transport of a large volume of flammable vapour over a built-up area is the greatest of the hazards of LJ?G in that it is liable to cause the largest number of deaths and most damage if it does occur. One cannot with confidence recommend to people that they close all doors and windows and stCJ.y indoors, as one can with toxic or even radioactive release hazards, since damage caused by a blast accompanying the flash fire can the houses and allow them to become ignited in many places. It has been stated that there are so many ignition sources in a built up area and then an' incomin9 clOUd of flammable gas \<lill be ignited before the flarrrnable vapours can encroach extensively into the area. It is difficult to accept this for a night time in purely residential areas. However, as will be indicated later, the controlled ignition of such clouds before they reach such areas could be a major defence against the hazard.

The second possible effect i.s the devel.opment of a mass fire as was caused by the bombing raids in Hamburg and Dresden. In this type of f:L.re the flames coal.esce to form a large column of flame above the area of the :fi.re. Gale force winds are established towards the fire and the upward buoyant column of flame may throw bUnling material to distances at points beyond the fire area. In general, to 2btain mass fire effects, it is necessary to have a burning area of at least 1 km and for buildings to be high and distances between buildings comparatively small, i.e. a fairly dense built up area. On the other hand, the furnishing at present in most dwellings, if ignited, can burn very rapidly and it may be possible that under these conditions even a mainly residential area of typical two storey high dwellings could allow a mass fire to be established.

Likelihood of Fire and ExPlosion Hazard

The fact that one can postulate catastrophic happenings as indicated above does not necessarily mean that storage and transport in the quanti ties indicated should be eliminated. Thus a possible catastrophic fire hazard exists for almost shopping complex in the country. There are hazards of this kind also for· hospitals, theatres, cinemas, etc. The question that arises is, is it really necessary to expose people to possible major hazards and if this cannot be avoided without difficulty, can the hazard be sufficiently reduced so that it beComes least endurable? It must be remembered here that a major factor in the capaC1ty to endure a hazard is the extent to which those at risk receive benefit from the hazardous activity. '!bus in the aboVe quoted examples of catastrophic hazard, those at risk are those using the premises not those outside.

No ope would deny that the community as a whole obtains great benefit from the availability of LPG fuels; the use of them in the liquefied fom is very convenient, particularly in small quantities in places which piped fuels cannot reach. Moreover in these days of energy scarcity, one must be mindful of the value of these liquefied gases as a substantial contributor to our energy resources. This particularly relevant in this country since North Sea resources have . unUSUally high content of these volatile gases. Indeed for this reason there loS a gOOd case for the consumption of liquid flammable gas to increase by a facto: of 5 or more over the next decade or so. For this reason also it is very appropnate that one should take a very rigorous look at the hazard presented by LPG at the present time and particularly to look for areas where safety might be improved.

Table 2 gives information on the occurrence of fire in the UK in which LPG was a contributory factor. For comparison, information is also given on fires in either. natural gas or town gas was a contributory factor. It contains numbers 07 fires Ul which the fuel appliance was the ignition source and also numbers which fuel itself was the material first ignited. In addition, numbers are g;L ven where both the fuel appliance was the ignition source and the fuel itself was the first ignited. :u: themselves, these figures are not very meaningful. They need to be compared each case with the amount of fuel used in the This information may be obtained from the annual abstract of statistics and is g:l.ven in Table 2. It may be shown that in all categories for all the years petroleum gas produced many more fires per million theJ:mS of fuel used than did natural gas or town gas. Perhaps the most relevant comparison is for fires in which the fuel gas was the material first ignited. Table 2 shows that the WhOle period LPG was about ten times more hazardous than the gases. Indeed the in the table are for fires in buildings only; taking account of outdoor fires would increase the LPG hazard by some 50 per cent. Another· disturl;l1ng feature is that there is little evidence that this fire rate is dt:!creasing as it undoubtedly is for natural gas. There are of course some good :ason$ for this, particularly increasing amounts of natural gas, which has. become Ch Jtlore avallable, are being used for central heating which is a comparatively safe way of using fuel. }breover all natural gas is piped whereas the vast bulk of fuel gases used are in stored fom to the appliances. Also, as l.Ildicated above, liquefied petroleum gases suffer from the disadvantage of

being heavier than air. The figures nevertheless point to the need for a substantial improvement in fire safety of liquefied fuel gases if their use is going to increase.

Turning to the major hazards, fortunately our in this country of such disasters with LPG as is indicated is virtually although there have been a significant number of near misses. The sort of thing which could happen is exemplified by the Flixborough disaster but this of course involved cyclohexane, not liquefied petroleum gas. A major feature of this type of hazard is that, unlike the individual LPG appliances relevant to most of the statistics in Table 1, and indeed also unlike the catastrophic fire hazard associated with buildings, those exposed to the hazard may be obtaining only marginal or even sometimes negative benefit from the activity. This applies particularly where large quantities of flammable liquid gas are transported at terminal areas; a risk can be stated to be almost focus sed at those people living near these places.

In order to make design and planning decisions, we need quanti tative infoz:mation on how safe we are from catastrophes of this kind. Techniques are now becoming available to allow this to be estimated through procedures known as hazard analysis and fault tree analysis. In the latter procedure the projected catastrophe is the final incident in a chain of unlikely events Itlhich lead first to the spillage then the evaporation with then ignition and either flaming or explosion, or both, taking place in an area where great harm can be done. Under the Health and Safety at Work Etc. Act, it is being proposed that organisations which store quantities of liquefied flammable gases in excess of 300 tonnes shall carry out hazard surveys and in certain instances where communi. ties might be at risk, to follow this up with a more detailed study which might include fault tree analysis. A recent example of a detailed survey has been carried out by the Systems Directorate on the Canvey Island situation. In my department at the University of Edinburgh for over the last four years we have carried out fault tree analyses "for three special situations: two of these are listed and summarised in Table 3. The third is an attempt to obtain fault trees for a major spillage in road and rail transport which is still in progress; this latter study suggests that tinder present conditions a major disaster will occur about once in 20 years.

Unacceptable and Acceptable Hazards

Havin9 obtained estimates of the above, the question arises, under what conditions is the hazard unacceptable'? There is much controversy as to how one shOUld approach this problem at the present time. One approach is ·that if the analysis shows a hazard which is not greater than that of a similar kind which has been endured in the past, then this is evidence that the hazard is not unendurable. However one must be very careful in postulating the factors which will allow us to say whether the known endured type of incident is indeed one of a similar kind. The characteristics of a major incident involving fire or explosion with LPG are that it will kill by fire in a short time many of the people exposed to the risk; but in some cases those facing the risk welcome the activity, in other cases they neutral and in others antipathetic. Data which would assist in developing quant1tative criteria may be obtained by studying our present risk of exposure to catastrophic fire and explOSion hazards. The evidence from such a study that I have carried. out indicates that at present a of some 10,000 people, for ffi1ght expect a fire disaster that would kill more than one hundred people and caused by a risk to whose benefit they are neutral t about once in 10 million years. A difficulty with probabilities as low as this is that it is below the range of probabilities that may be confidently predicted by fault trees at the present time. However, it suggests that a criterion for acceptability of the order of once in 10,000 years implied by the Canvey Island report is too high.

Methods of Improving Fire Safety with Ll?G

General Hazards

The poor record of LPG with regard to fire occurrence compared with piped gas prompts one to look for possible ways of ilnproving its safety. Unfortunately, it is not obvious to find these. The high fire rate would appear to be inherent in the places and manner where Ll?G is used and arise because of the sheer convenience of using bottled gas. Good Codes of Practice, such as the Home Office Codes, have been available since 1971 and LPGTA have provided much guidance on this matter. Their effect might well begin to show in future years. The situation shoUld also improve when regulations under the Health and Safety at Work Etc. Act are produced with accompanying Codes of Practice for different industrial situations. A possible general improvement that might be affected is to recommend that flammable gas detectors be employed in the vicinity of LPG appliances. The provision of a mass market for such detectors could well result in a cheap reliable in a way similar to the mass market for smoke detection has developed 4n the United States. They could actually be fitted on appliances and set to give a warning or shut off a supply or even open extra ventilation if high concentrations of flammable gas is detected.

A major step forward, particularly if the use of LPG is to be increased, is to move the use into the direction where there would be less handling of cylinders, particularly towards piped gas. Another possibility is to use LPG for road vehicles. Here the hazard would need to be comparable to that of petrol if such a use was not to give rise to special anxiety on fire safety. There are reasons for believing that in some respects the fire hazard would be greater than petrol, e.g. the influence of a fire near the tank as a result of a leak. Even though the !.PG tank may be. vented, this is unlikely to prevent a substantial fire inside a vehicle when the vent operated. Also, overfilling is more likely to lead to accidents. However the tank would be more robust than a petrol tank and less likely to be damaged in a collision. A detailed hazard survey would be valuable before this were to become extensive in the UK, perhaps with some full scale tests as well the effect of fire. LPG is being used widely for cars in Europe, particularly where 450,000 tons per annum are being used for road transport. An to the Dutch Research Institute for Road Vehicles has indicated that experience in Holland has not given reason for special concern.

Major liazards

Can we do about the major hazards associated "dth storage and trcu;sport of quantities of a few tons upwards: The relatively clean record Ul t.h? UK far should not blind us to the risk that exists, not only to the population large but also, and perhaps particularly, to emergency services called to eal with an incident. As far as road tankers are concerned, the recent regulations requiring them to carry a warning panel which includes instxuctions emergency action, goes some way to reducing the hazard to which they a:e exposede Code 2WE for butane and propane indicates that there is danger of a explOSion, they should wear full protective clothing and use water fog as a medium; they should also consider evacuation of the publiC. "vi no indication of how far away danger would be manifest if there s a o ent explosion".

American experience of incidents involving a road or rail tank7r and by fire, is that there may be only about 10 minutes before a expl place. The latter is an acronym for "boiling liquid expanding vapour The but really corresponds to the fireball situation outlined in Table 1. on su hOrmation in the table suggests that if firemen are called to a fire incident c a tank . all as the er, they would be unwise to approach within 300 metres, y heat called full protective clothing is not a protection against • ey almost certainly would in order to set up some cooling

onto the tank, particularly if many people were at risk,. in so tI;ey a:e themselves taking a risk. Even if there is no leak followJ.ng an :lll which an LPG tanker is involved in violent collision, there may be c;iarnage, possibly unseen, to the tanker which could result in strength being below that of the pressure release and its sudden Thus there that the unexpected BLEVE at Waverley, Termesse, last was due to. the scoring of a rail tanker which had been derailed. It is my that a major step towards reducing the possibility of incidents of this kind would be to transport LPG and indeed other dangerous materials like it, in the refrigerated state in containers. The safety would be improved by reducing the temperature to well below the normal boiling point. This practice should eliminate BLEVES and pressure bursts of the above kind. Also, in spite of the mistakes made in the recent Spanish disaster, it almost certainly would not have occurred if the liquid had been transported in an insulated container. Such a change would bring about some changes in the fuel as used in practice cmd would cause extra expense. However, a fundamental reassessment of the way LPG is handled is timely if there is likely to be a sharp increase in its use. For example, if LPG is to be used as an automative fuel, it could be transported in the refrigerated state, stored in the garage in this stage and warmed sufficiently on it being delivered to the fuel tanks of vehicles, if this is indeed necessary 0

"'lith regard to very large tormage stored in refrigerated tanks on land, here at least a step towards safety has been taken by reducing the liquid temperature to its boiling point. One still has the possibility of failure of the tank but the state of the liquid allows a very important safety step to be taken, i.e. that of redundant secondary containment. This means putting a second container round the first, which will hold all the "liquid if the first container fails. The structure of the redundant containment should be such as not to fail by mechanisms whicn cause failure of the first (mainly rollover and metallurgical failure). An outer shell of concrete is therefore appropriate for the task.

Gas Tankers on Ships

This still leaves the thorny question of liquefied gas tanks on ships. In addition to the mechanisms of failure indicated above, these have certain more likely fai 7ure These ships move about in inshore waters where they may be subject to and stranding and they are often in direct contact with a terminal where there is a significant probability there could be a leak or overfilling, or some other maloperation that might cause spillage. There may be ignition sources on or near ships. In addition the management of ships W be heterogeneous and not. the same degree of diSCipline and caou-ol 8S land based managemE'.nt. To cap it all, there :1.1"1 c;l.QCC prl"lxi.m.ity much water with which these liquefied gases are thermally incompatible and which could enhance a spillage hazard by causing rapid Vaporisation.

A simple solution would be to keep these tankers away from highly populated areas. Table 1 suggests that a distance of about 6 km or 4 miles would be reasonable. Although this is within the maximum distance of spread to the LEL, it is unlikely that a large area that would maintain a flash fire Would build up outside this distance for a leakage up to 1000 tons. What is perhaps more import9Ilt is that this distance will allow a flexibility of emergency operation if there is a dangerous incident which results in a tank being punctured, particularly under water. Thus if the vapours of such a leak are not threatening people, the safest way of dealing with them is to allow them to on their own. Owing to the possibility of a sudden intensification of the incident, resulting from the possible entry of water into a tank, I would recommend immediate evacuation of those on board and exposed to the vapours and would advise that emergency services should not approach unless they are protected against being surrounded by fire and exposed to explosion forces. However, if the vapour leak becomes so large as to develop into a threat to people on shore, partiCUlarly in a built-up area, then I think it would be necessary to

ignite the leak. This will result in a flash back to the and a fierc:=e fire there. The evacuation of personnel is a necessary to allow this option to be exercised. However, the dimensions of the near the ship, although great would be much less than the maximum flash area indicated in Table 1. Thus'for 2,000 tons of LPG leaking in 13 minutes, the fire would be about l30rn diameter and 360m high; for 20,000 tons escaping in 26 m;urutes, 300rn in diameter and 600rn high. Even the occurrence of a fireball during. such a fire as a result of a 2,000 ton tank suddenly dismpting is unlikely to endanger people at a distance of 6 Jan. However, the liabllity of SUch. a tank to at any time if water can gain access to the tank will comprom1se the of emergency services to call for an evacuation to a safe distance in an emergency situation for distances less than about 4 Jan.

As things are at the moment, these tankers move well within this 6 km distance. Can the risk in this situation be reduced to endurable levels'? Nanagement at term.inal.s and tankers could be tightened, e.g_ only one management could be respOnsible for both. Also tankers could be· used which are designed so as not to puncture or spill contents into the sea, under any conditions of stranding, or process maloperation. Judging fmm the Canvey Island report and our own hazard analysis for an LPG terminal given in Table 3, there appears to be a long haul before this approach becomes eanvincingly viable, bearing in mind the criterion for acceptability implied above rather than the one adopted in the Canvey Island report. It should be noted here that the 1975 Intel:national (DCO) Standard allows the use of both integral and membrane tanks for liquid butane and propane respectively and actually visualises the puncturing of tanks and their becoming filled with water as a possible condition for the design of the stability of the ship.

Contributions to safety might be made by chilling a liquefied gas cargo to a temperature well below its boiling point and surrounding the tanker at the terminal by a boom which will reduce the extent of spread of spilled liquefied gas. If there is a substantial spUlage this would cause ice to form under the spillage and considerably reduce the rate of vaporisation which is the dangerous factor in this situation. Moreover, if there is a puncture in a tank which results in water invasion, the lower temperature of the Ll?G would encourage the rapid formation of ice without vapour formation soon after the water ingress and therefore considerably reduce the possibility of explosive formation of flammable vapour ,in the tank. However, much research is required to establish optimum conditions for this reduction. Even without extra chilling, a boom set up some 20 metres away from the ship's side attached to each end of·the Ship and strengthened and perhaps compartmented with supporting spokes to the ship's side, would valUable independent secondary containment for many spUlage situations. 'Ihe vapour would not be held back but its rate of production would be reduced and would probably become controllable by emergency measures e.g. the automatic action of medium· or high expansion foam generators. Indeed it would be desirable for such ships to carry such a boom while moving near populated areas, al though this may result in stmctural and navigational diffiCUlties it could be made to act as a first line of defence against a lateral COllision. 'Ihe boom may be kept on deck for passage through the high seas and lowered for inshore waters.

Beyond this, if there is any residual unendurable risk to exposed residential areas, there is little one can recommend other than to give the houses the necessary degree of fire and explosion protection and to compensate injured Parties for to excessive risk and anxiety due to risk. It must be remembered that anxiety is caused not only by possible accidents affecting the injured parties directly but by catastrophic accidents that may happen anywhere in the world _ particularly if it cannot be clearly demonstrated that conditions are significantly different. The type of protection that would be relevant would be:-

(a) A warning system which woul.d give warning of imminent danger due to a major spillage having occurred, or some other reason.

(b) Emergency procedure including notice of what should do in the event of a warning. This would include instructions on how to seek refuge or to evacuate.

(c) Provision of a controlled ignition source flammable gas detector system to ignite flammable gases if they approach the shore.

(d) Provision of fire retardant shutters or curtains for windows of premises under threat of fireo

(e) Provision of treatment for splintering of all glass under threat of explosion pressures and not protected under (d).

(f) Provision of sprinkler installations for all premises under threat of fire.

(g) Provision of safe refuges against explosion or fire effects.

Conclusion

1. 2. 3. 4. 5.

Liquefied fuel gas is a valuable fuel resource which is likely to increase greatly in availability in future years. However special efforts are needed to make its use sufficiently safe with regard to fire and explosion.

The fire and explosion hazard of LPG in its everyday use is intrinsically more difficult to counter than that of town. gas or natural gas. The reasons are:

(a) that LPG vapours are heavier than air;

(b) the gas is provided as an article of conrnerce rather than in a piped system;

(c) because of its special convenience it is used in situations where it is not easily subject to control.

Available statistics on fire indicate that LPG is more than ten times more likely than natural gas to cause fires and explosions per unit energy use of fuel.

FUture major expansion of LPG should take place in direction of piped fuel or into situations which do not require exchange and trading of gas cylinders. A detailed hazard survey is justified prior to any ir d extension in its use. fVJOre extensive regulations and codes are also requ e.

LPG as used at present has attached to it a very serious propensity for major fire and explosion hazard. This is due to the ability of the d liquefied gas to vaporise very rapidly when containment has been 1 ly thus prOduce massive vapour clouds in a short time. This applies P cu ar to the pressurised liquid at ambient temperatures for which secon?ary cc:>ntainment is generally impracticable, but also, under some conditions,. t to the refrigerated liquid at ambient pressure for which secondary contaLnmen generally practicable.

6.

TOe hazards result from the possibility of a large fireball which would occur !i ignition followed soon after release, or fire or explosion, in an open toammable cloud, if ignition was delayed. Perhaps the greatest hazard would OCcur if a flammable cloud drifted over a populated area and ame l.gnited.

7. In the UK there is no experience of a major disaster of the type outlined .in 6. However, hazard surveys ava..i1able .indicate that: the .l.j.kQlihood of such a disaster is quite credible.

8. Reduction of major hazards in road and rail transport could follow if LPG were transported inthe refrigerated state particularly if the temperature was well below the boiling point at ambient temperature. There would however be economic disadvantages of doing this.

9. Both pressurised and refrigerated tankers (ships) should, if possible, be kept well away from populated areas, both to prevent a disaster and give flexibility in an emergency situation. If in the national interest it is not possible to do this in certain instances, then it is necessary to reduce the risk of a major disaster due to fire or explosion to a leVel below that which appears to be the case at the present time. This can be done by:

(a) Improving management and design of tankers and tenninals so that spillages will occur at a far lower expected frequency.

(b) DeVising methods of reducing the rate of vapour foIltlation from the spillage, particularly by containment.

(c) Providing special fire and explosion protection to those exposed to the risk.

There may also be a case for providing compensation to some of those exposed to the risk.

References (2)

Hazardous Installations (Notification and Survey) Regulations 1978. Health and Safety Commission Consultative Document. ' Canvey An Investigation of Potential Hazards from Operations in the Canvey IslandlThurrock Area. HMSO 1978.

(3)

Code of Practice for the Storage of LPG at Fixed Installations, HMSO 1971.

(4) Fire Prevention Guide No. 4, "Safe Use and Storage of LPG in Residential Premises". HMSO 1976.

(5) D. Barber. "Safety with LPG"o 18th Annual Week-End StUdy Course 1978 The Environmental Health Officers Assoc., Yorkshire and Humberside cenh-e.

( 6) for the Construction and Equipment of Ships Carrying Liquefied Ga J.n Bulk. Inter-Government Maritime Consultative Organization. London

(7) HSE "A Guide to Tanker Marking Regulations". HMSO 1979.

(S) N. Kemp and D.D. Drysda1e, "Designing for F1arrmable Atmospheres in Buildings". Architects' Journal 1979.

See also references attached to Tables 2 and 3.

Table 1: Major Fire Hazard Following Spillage and Vaporisation of Liquid Flarrrnable Gas

Tons 0:1. 1 Storage I No rapid ignition- Ignition soon after spillage and vaporisation+ liquid quantity vapour typical of:- Max. spread Max. area Spillage Maximum hazardous conditions formed of flarnm. of flash time to vapour fire if produce Properties of Fireball Effects of Fireball downwind ignited maximum effect Fireball Time of lRadius for Radius for Radius for radius duration spontaneous pilot unbearable km 2 <Irln ignition ignition pain km km s km km km 2 Central heating storage (pressurised) .3 .01 1.5 .029 4.2 .08 .10 .19 20 l'1oderate size tanker ( pressurised)- .9 .05 3.0 .06 6.4 .21 .26 .51 200 Small size storage sphere (pressurised) 2.6 0.3 605 .12 9.8 .58 .74 1.55 2,000 Tank of ship's cargo (refrigerated) 8 2.0 13 .25 14.8 1.6 2.1 4.4 20,000 Refrigerated tank on land. I Refrigerated i I ships's cargo I in a number i of tanks 24 12 26 .52 22.5 I 4.3 5.8 13.2

+ Fireball radius and duration based on ref (1). Radii for various effects based on tie assumption that 2OC"{' of the total energy of the fireball is radiated within the duration time of the fireball. Tt.is is the mean of a value of about 15-20% that might be infe.c:ed from the data in ref (1). and the 24.4% reported in ref '2). For pilot and spontaneous ignition data from Ref (3) taken for fibreboard was for unbearable pain data from Ref (4). • Based on information provided by GoD. Kaiser _ Ref (4) •

K. Hasegawa and Ko Sato, "Experimental Investigation of the Unconfined Vapour-Cloud Explosions of HydJ;:ocarbons". Techn:i.cal Memorandum of Fire Research Institute No. 12, Tokyo, 1978.

G.H. Markstein, "Scaling of Radiative Characteristics of Turbulent Di.ffusion Flames". FMRC No. 22361-4, 1976. Factory MJtual Research.

DeI. Lawson and D.L. Sirnrns, "The Ignition of Wood by Radiation". British Jnl. of Applied Physics, Vol. 3, September 1952.

D.L. Simrns and P.L. Hinkley, IIProtective Clothing Against Flames and Heat". Fire Research special Report No. 3, 1960.

Canvey an Investigation of potential Hazards from Operations in the Canvey Island Thurrock Area. Appendix 9.

Fire Statistics LPG, Natural Gas (NG) and To1Nrl. Gas (TG)

(Taken from Armual Fire Statistics)

1977 1976 1974 1973 : 1972

Number of fires z material first: ignited:

In buildings LPG TG + NG Not in building LPG TG + NG

Number of fires, source of ignition:

1113 894 912 13(;2 1357 1608· (not available)

844 967 1644 : 1846 624 502 346* 560*

1971 1970 541 632 1691 1613 503 427 622* 558*

:. : . . 1710 1631 1573 1406 1270 ' 1088 1080 7538 8776 8978 : 8333 7333 7107 (not available) 910 746 650 675 26 14 19 23 .'

Number of fires z both source : of ignition and material first ignited:

In buildings LPG TG + NG Not in buildings LPG TG + NG

Fire rate in buildings magerial first ignited! 10 theJ:InS NG and TG : used in UK (10 9 'lh) Number9 0f fires : per 10 Tb for NG and TG : !.PG Used in UK (10 9 Th)

418 914 282 o

288 859 217 2** .............................

287 760 178 3·* .'

424 817 207 3**

-0-· ......:........:........'....... ....... .............. . ::

. 10.700 . 9.757 : 7.440· 5.750 ; 153 180 225 280 .627 ; .516 .356 .268 '1346 . 1874 1519 2358

Table 3:

summaries of Fault Tree Analyses Involving Major !.PG Risks

Type of Horton sphere 600 : ton capacity. Protected by water system and an crew. Situated 150m from rain plant (ref 1)

Projected disaster

(l) Catastropmc fireball at sphere.

( 2) Open flammable cloud explosion plant following of cloud of unignited vapours

Liquefied gas marine : terminal handling : pressurised LPG. (Ref 2)

Major fire or explosion in the terminal area involving either catastrophic fire ball or large open flammable cloud or fire

Estimated probabiUty of disaster

(1) 1.7xlO-8/annum

(2) 2.2xlO-6 /annum

2.3xlO-3 /annum

Ref 1 D.D. Drysdale and G.J. David, International on Fire Safety Evaluation in Industry, Stockholm, 1979. pp 1-25. To be published in "Filre Safety Jouma1".

Ref 2 RoJ. Beckett "Fault Tree Analysis for the Operation of a Liquefied Gas Marine Terminal". MSc Dissertation Un1.versity of Edinburgh, 1978. Paper in preparation.

LONDON NEWS

A petrol pump was found to be knocked over when a licensee opened up his Petrol Station one morning. It was a little later that a young man came in apologiSing and accepting the blame. The explanation was that he thOUght the deserted forecourt

a good place to say goodnight to his young lady Unforturnately (for the licensee) the windows of the car became steamed up and he reversed into the pump knocking it Over as far as we know that was the only damage.

Panic

When petrol vapour was ignited whilst petrol was being drained from the fuel tank of a car on a hoist in an unlicensed garage workshop two mechanics ran to the rear of the building where an escape door was provided. In

their panic they ignored the escape door and ran up stairs leading to the first floor where they ignored another escape door and jumped out of window to safety.

In the ensuing fire the roof of the workshop and three cars were destroyed. The cause of the fire could not be established.

FATALITY ARISING FROM UNSAFE USE OF PETROL

C.W. Brudenell Chief Officer of Trading Standards. HUMBERSIDE COUNTY COUNCIL

2. The maximum quantity of petrol allowed to be stored by a private individual for his own use is 2 x 2 gallon metal containers (Excluding the fuel tank of his car). Storage above this amount or in larger containers must be notified to the local authority and fulfil requirements relating to distances from buildings and highways.

On a Saturday evening in August an explosion followed by a fire occured in a house at Withernsea. The householder, an elderly man, suffered serious injuries from which he subsequently died, whilst his wife is still slowly recovering in hospital.

An investigation by an officer of the department revealed that petrol had been stored in a 5 gallon metal drum, in the garage, at the rear of the house. Some of the contents of the drum were poured into a 2 gallon plastic watering can, in a small yard between the rear kitchen door of the house and the garage, with the intention of putting it into a new car. This car was parked in the street outside the front door of the house, to which there was access thrOUgh the back-yard door bl,lt this was locked. The householder decided to walk through the kitchen, dining room and front hall of the house to reach the car.

As he entered kitchen he tripped, spilling the petrol over his clothing and the floor. He took off his saturated Coat, putting it on a chair in the dining room Qut left his trousers

He then began to mop up the floor, w1th the aid of his wife, who had been preparing a meal using a gas cooker. The petrol vapour exploded, inflicting severe burns to both of the couple in the kitchen. Part of the rear of the house was blown down. The kitchen and pantry Were severely damaged by fire, as was the area of the dining room where the petrol Soaked coat had been laid.

This'1ncident tragically illustrates the rtheasons for petroleum storage laws and e need fo the law r strict observance both of and normal safety precautions.

Storage vessels must labelled "P t 1 , e ro eum Highly Flammable".

be metal and Spirit

The drum in this case, although metal was not lebelled.

In this case it appears that approximately 4 gallons of petrol were stored in the 5 gallon drum, which should have been kept at least twenty feet from a building, highway or public footpath.

3. Petrol should never be carried in an open container.

In this case an open watering can was used. This was also plastic, and petrol will dissolve some plastic materials, and harden and crack others.

4. Petrol should never be taken into a living area unless absolutely sary, and proper ,recautions observed.

On this occaSion the pe·trol was carried" in to the house when there was another, safer, route available.

5. Precaution must be taken to prevent exposure of the petrol to any fire or artificial light liable to ignite the inflammable vapour. In any kitchen there are several possible sources of ignition of flammable vapour.

6. When petrol is accidentally spilled on clothing, the clothing should be : immediately removed, hung in the open air until all trace of petrol has and then thoroughly washed. In this instance, failure to do so was a contributory factor in the fatal injuries, and spread the fire to the dining room.

In times of scarcity of petrol and for other reasons it is apparent that many persons unthinkingly put themselves at risk by storing and dispensing petrol in conditions which are not only illegal, but hazardous to themselves and their neighbours. Equal care must be taken with petroleum based products such as adhesives.

APPEALS

Kent County Council

On the re-organisation of Local Government in 1974 the administration of petroleum legislation was transferred from 47 District Authorities to the Kent County Council Trading Standards Department.

The quality of the existing licenced premises was extremely varied and careful consideration was given to the imposition of a limited life on certain sites which could not be brought up to a reasonable standard, bearing in mind the Home Office Model Code.

A number of sites were examined and licensees advised that their licence would not be renewed after a certain period of years. With the advent of the; various fuel crises since 1974 many of these premises have ceased storing petroleum of their own will.

However, two premises that continued to store petroleum decided to appeal against the decision of the County Council to refuse to renew their in 1979.

In the first instance the licensed premises consisted of a village shop dealing in motorcycles, accessories and electrical goods. Outside the shop on ei ther side adjacent to the building and on the pavement stood two fairly modern petrol pumps with swing arms. The premises stood on a main road with a moderate flow of traffice including a number of heavy commerical vehicles. The storage tanks were situated in the open air at the rear of the premises and consisted of two 1,000 gallon and two 500 gallon tanks. To replenish the underground storage tanks it was necessary for a road tank wagon to either reverse in or out of a narrow passageway adjacent to the ShOD. On the opposite side of this was a private dwelling house.

Grounds for refusing the renewal of the licence were based on the following:-

(1) Both pumps were situated on a narrow footpath and within 14 feet of the doorway of the shop. In consequence inflammable vapour was exposed in an area over which the licensee had no effective control.

PETROLEUM LICENCE APPEALS IN KENT

by DAVID GRAHAM HUMPHREY-WOODWARD Divisional Trading Standards Officer,

(2) Vehicles were refuelled from the pumps by means of swing arms across the footpath whilst the vehicle stood in the roadway.

(3) No petrol interceptor was provided to contain any spillage from pumps, ·cars or tank vehicles.

(4) A compressor was 'situated within 14 feet of the pumps.

(5) The shop had a cellar beneath it in which inflammable vapour could collect should there have been a spillage.

(6) The petrol tank wagon stood in a narrow passage whilst delivering to the storage tanks and it was necessary to reverse either in or out of this passageway.

With all the above points, except No. 4, no improvements to the storage itions could be made.

Subsequently, the licensee lodged an Appeal with the Health and Safety Executive and this was heard before Dr. C. Johnstone, one of HM Inspectors of Health and Safety, at Sandwich in March 1979.

The appeillant basea his avpeal on an accident free history of the premises for a period of 12 years and the hardship which would result from the loss of the licence.

Dr took the opportunity of the site and then submitted h1s report to the Secretary of State.

In July the licensee was Qdvised of the result of his appeal which was dis.allowed.

In the letter to the licensee the observations of Dr. Johnstone were made on each of the County Council's six points. It was noted that Dr. Johnstone saw little danger from most of the points raised by the County Council but saw fit to refuse the appeal on the following grounds:-

(1) Any leakage of petrol from the underground storage tanks (two of which were 40 years old and subject to a bi-annual leakage test) could penetrate the ground and possibly enter the adjacent cellar thereby creating a dangerous atmosphere where there were sources of ignition.

Further the danger increased since there was only one exit (into the building) from both the cellar, where electrical repair work was carried out, and from living accommodation at first floor level.

(2) The exhaust ends of the vent pipes discharge downwards and this could create a potential hazard on a still day with a dangerous accumulation of petrol vapour in the yard at the rear of the premises.

He continued that it was recognised that the main danger at any petrol installation arose from the spillage of petrol and subsequent ignition. Spillages have been known to occur when fuelling vehicles as a result of (A) leaking delivery hoses or pumping equipment, (B) overfilling a vehicle's fuel tank, and (C) passing vehicles colliding with one being fuelled.

However, the Inspector saw no reason to believe that spillage from cause (A) would be likely to occur at these premises as the 9umps and their ancillary features to be well-maintained, and free from leakage.

from cause (B) were in any case.usuall y small and that these prem1.ses would be tnilikely to reach the publi th f c drainage system. He, ere ore d· C t '1.d not support the oun y COunCil's view that an interwas essential at these prem1.ses. The 1 depended ikelihood of cause (C) of the t on the speed and density side th raffic on the roadway outular inetPremises. In this particf he considered the rh;}; o 1.S1.on Was high and in his opinion, there were factors which gave rise for serious cern so far as these premises were

(i) The pump at tendan t was in danger when the filling point was on the offside of the vehicle.

(ii) When the filling point was on the offside the suspended delivery hose was liable to interference from any large vehicles passing close to the stationary vehicles. If the hoses were disrupted spillage would almost certainly result and the pumps could even be unseated from their bases causing danger; and

(iii) During filling operations passing traffic was obliged to encroach on the opposite side of .the road to avoid the stationary vehicle. If a large vehicle made a wider than usual sweep it would obstruct the width of roadway to oncoming traffic and this could lead to collisions.

However, the appeallant then sought Council's Opinion as to whether he had a further right of appeal and if his grounds were justified, After a period of time he withdrew notice of this further appeal and has taken steps to dispose of his existing stock of petrol during the extension of the licence granted by the County Council.

The second licensed premises consisted of a car situated on the corner of a 'T' junction in the main High street in the town of Deal. Within the showroom were both of the 500 ballon underground storage tankS and the two petrol pumps. The decision of the County Council to refuse to renew the licence was based on the following points:-

(1) Both pumps were situated within the building and within 1.5 metres of the footpath.

(2) Vehicles were refuelled from the petrol pumps by means of swing arms over the footpath whilst the vehicle stood on the highway. The licensee had no effective control in that area.

(3) The two 500 gallon underground tanks were situated some 2.5 metres within the building beneath the car showroom.

(4) The petrol tanker stood on the highway when delivering into the underground tanks.

(5) No petrol interceptor was provided to contain any possible spillage from pumps, cars or tankers.

(6) The vent pipes from the underground tanks discharged onto the footpath.

(7) The licensee was unable to comply with certain conditions of the licence in connection with the prevention of spillage into drains, a fire or explosion by persons passing the premises, and possible sources of ignition.

Again the appeal by the licensee was he ard by Dr. J ohns tone in March 1979 with a visit to the premises.

The licensee appeared in person and submitted that considerable goodwill was attached to having petroleum for sale at the premises; that there had been an accident free record; and one employee would be made redundant.

The Inspector again made reference to the three most common occurrences of spillages when vehicles are being refuelled as detailed under A, B and C aforementioned. He stated that cause A, leaking delivery equipment, could be avoided by compliance with the Council's licence conditions; caUse B, accidental overfilling of vehicles, usually resulted in small quantitieS and in this instance were unlikely to reach the public drainage system; and with cause C the risk of collision was low owing to the low volume of traffiC and nearness to the 'T' junction where vehicles would not be moving at speed.

With reference to the grounds for refusal by the County Council the Inspector commented that there was no remarkable history of accidents occuring during fuelling operations where pumps were situated inside the garage, even though the licensee had no control over the actions of passersby who migh t introduce igni tion sources. Having regard to the fact that refuelling takes place only 8-10 times per day he did not accept that the

resiting of the pumps was essential for public safety.

The Inspector felt that any spillage of petrol which might occur when the underground tanks were replenished inside the showroom (every 4-6 weeks for a period of 20 minutes) would be retained in the manhole chambers and, therefore, saw no danger of it reaching the public drainage system. Since major spillage was unlikely he did not support the Council's view that an interceptor was essential at these

The view of the County Council that a dangerous concentration of t _ pe rol vapour from the vent pipes Could accumulate on the footpath '. or l.nSl.de the bUl.ldl.ng themby giving . rl.se to a potentl.al hazard under cert . d · t' al.n con l. l.ons was supported by Dr. Johnstone. However he t ' sated the rl.sk could be alleViated b extensions of the pipe work f y rom the footpath and with the e h . x aust ends to dl.scharge Upwards.

In conclusion the Inspecto d r rew attentl.on to the minimal u sage of the pumps and pOinted out th side fuelling was not in i at kerbobjectionable feature. Altself an the installation was a showroom, ignition l.nSl.de sources minimal. Therefore, Sub' Were two modifications th Ject to , e app upheld and the County was the Health and Safety E Cl.l, not were obliged to Cont.l.nuexecutive l' , the premises. l.censing

The above is a summary Appeals heard in Kent of the two analysis of both CarefUl indicate that most f tend to o the put forward by the C POints Ounty C were not substantiated ouncil Inspector. His pr by the ecedent to be based on (1) th appeared vehicular traffic e VOlume of 1 pasSing l.censed premises. and the aSSOCiated risk f the o cOlli . vent pipes disch Sl.on; (2) arging d where there was . ownwards a rl.sk of' . and (3) undergrOund t l.gnl.tion considerable age whi anks of a leak and pen t ch may develop cellar. e rate an adjacent

Hopefully th ese notes may guide other Petroleum Officers in their assessment of whether to terminate a licence for an apparently unsatisfactory site.

ANNUAL GENERAL

MEETING

MINUTES OF THE ANNUAL GENERAL MEETING HELD AT THE WEST MIDLANDS FIRE SERVICE HEADQUARTERS ON WEDNESDAY 25TH APRIL 1979

The meeting was opened by Mr. G. Bailey, Chairman' of the Association who welcomed 41 members.

1. Apologies

The Honorary Secretary reported 54 apologies from members who were unable to attend.

2. Minutes

The minutes of the 1978 Annual General Meeting (Previously circulated) were put to the meeting. It was unanimously agreed that these be accepted.

3. Matters Arising

There were none.

4. Chairman's Report

The Chairman in his address welcomed the members present to the meeting, and on behalf of the Association, thanked the Chief Officer and his staff of the West Midlands Fire Service for their kindness in the facilities for the meeting. He spoke of his year of office as being a pleasant one during which he had received much support and assistance from the Officers and other Members. He continued at some length to summarise the current position of the Association, and went on to inform members that two of the ASsociation's Officers had indicated that they would not seek reelection for the coming year. He said, that whilst he very much regretted the loss that this would represent to the AssoCiation it would allow for .' , a. revl.ew of OUr position and future' dl.recti id on, and would perhaps permit eas that would enhance the u ure POliCies of the Association. The Chairman closed his address by thanking Members for the honour that had been paid to him, and gave his best wishes for the future progress and development of the Association.

5. Honorary Secretary's Report

The Honorary Secretary first reported upon the membership position stating that membership presently totalled 146 Members, 106 Associate Members, 12 Honorary Members. and that the Bulletin had 35 Subscriber Members.

These figures he said, represented a reasonably stable situation, but he felt that all Members should make a further effort to preach the gospel and by so doing aim to increase at every opportunity. He went on to tell Members that during his year of office he had received a continuing volume of requests for advice and information, and he felt that this served to emphasise one of the benefits of an Association such as ours. He informed Members that again, due to the demands for economy, there had been no Council meetings during the year, all of the Council's business being conducted by telephone or correspondence. He said that he hoped this situation would change in the future, for he felt that if the Association was to expand its services to its Members then full participation in the Association's affairs had to be accomplished by the Council' and its' officers otherwise there was a danger of it becoming a one man band. The Secretary told Members that during the year, he had been asked to give a paper to a seminar organised in London by the Health and Safety Executive. This had he felt been successful and many of our Members present at the seminar had been able to air their views on many topics concerning petroleum legislation. The Secretary added that he had attended two other meetings with the Health and Safety Executive in London at which discussions took place concerning the future trends of petroleum legislation neither of which provided firm information on the future direction of such legislation.

The -Se ere taryspoke briefly about the present Branch acti vi ty, and told Members that whilst both the Eastern and Yorkshire Branches were growing in strength and activity. The South Eastern Branch appeared to be in some difficulties. He hoped that he could be of some assistance to them in ironing out what he felt were soluable problems.

Finally the Honorary Secretary spoke about his decision not to seek reelection. He told,Members that his appointment to the post of County Safety Officer for Cambridgeshire were increasingly involving him in activities away from petroleum legislation, and that he was finding great difficulty in reserving time to carry out his Association duties. This he felt was wrong, and unfair to the Members who very naturally look to the Secretary of any organisation for some measure of leadership. Further, he felt that whilst he had enjoyed his work for the Association ten years was enough in the view of some Members perhaps, more than enough, and he believed that a new Secretary coming fresh to the task would inject new life into the Association's activities.

The Secretary concluded his report by thanking the arid Members for their unstinting assistance during his year of office.

6. ____ Treasurer's Report

The Honorary that the Association was in a reasonably satisfactory position at the end of 1978 and thanked the Chairman, Honorary Secretary and Honorary Editor for their aSSistance in keeping expenses as low as Possible. There had been no increase in the rate of subscription since 1977 but a small increase may become necessary in 1980 if the continual increase in t absorbed. cos s can no longer be

He reminded members that the Inland Revenue Authority recognised this association as long ago as 1975 so that all members and associates who pay their subscription may deduct it from their emoluments.

He requested the dilatory payers to forward their subscriptions more promptly.

7. Honorary Editor's Report

The Honorary Editor, Mr. J.S. Crewe, reported that since the last AGM of the Association, When he had had to report the printing of only three issues of The Bulletin, we were once more on schedule, with four issues having been produced during the curren t ye ar the present one being with the printers: Production of our journal was now progressing more smoothly than ever before during his tenure as Honorary Editor, he reported, and he was therefore doubly sorry not to be standing for re-election, a

matter he would refer to in more detail later.

During the year some new Bources of copy for 'The Bulletin' had emerged, and new itmes had been produced from these. Mr. Crewe mentioned 'New Publications from the BSI', 'News from the HSE' and 'London News' as examples of these, and cited other individual items which had been proffered by contributers, following his appeal for copy at last year's A.G.M. and at Eastern Branch

The standard of these had been very high, he said, and he hoped that this would encourage others who were a. little reticent to put pen to paper to 'have a go' The latest new advertiser, the Honorary Editor reported were K.D.G. Instruments, who had in fact began advertising before the last A. G. M. but who had not been reported by him then. There was, however, space available for many more advertisers and he urged Members and Assocaites to recruit any company Who might find benefit from exposure in the pages of our magazine"

In Volume 17, number 3, a correspondence column had been started, Mr. Crewe said, with th aim of encouraging interest and e controversy among readers. The intention had been to make th" "t 1S a regular 1 em, even though the difficulties of continunit h " d" Y ad been 1n a quarterly format Journal. Unfortunately n o one had picked up the and no fur correspondence had ensued h" ther " , w 1ch Wa the Honorary Ed1tor felt s, "' ' SOmething of a P1ty. The majority f o OUr members do not appear to be let writers', he commented ter In passing, the Honorary Editor reference to some complementar of 'The Bulletin' which y 1Ssues were Sent t quarterly. These were to other ou journals, such as petrol magazines, 'The Monthly house the like. A copy of thes V1ew' and was sent to him in h" e magazines 1S capaci t editor, and he was occasio y as to use items fro th nally able Th m ese journals with permission. us, a copy of our' magazine was sent to each of th bl " t" " ese pu 1ca 10ns 1n return.

Mr. Crewe reported that his would be his last report to the Association as Honorary Editor. He apologised for his poor timing in standing down at 'the same time as John Frid, Na:tional

Secretary. It had originally been his intention to stand for election for a fUl"ther year, he said, to save the Association the double upheaval of electing a new Honorary Secretary and Honorary Editor at the same time, but circumstances had made this course of action an impractical one. Like John Frid, he reported, his work was now outside the mainstream of Petroleum and Explosives enforcement, and in addition, the office organisation of his new post meant that he now received no outside support at all in producing the Bulletin. He cited as an example the fact that his letters to contributors etc. had to be hand written. He did not wish to see the Association represented in this way, and he had therefor.e, regretfully decided not to stand for re-election.

He had, he said thoroughly enjoyed his term of three years as editor of The Bulletin. Finally he wished to thank Bob Holdaway, John Frid, and Cliff Peacock for their help and encouragement during this time and all contributors and advertisers for their support.

7a Additional Items

At this POint in the meeting the Chairman informed members that because of procedure problems, he would have to vary the printed Agenda in order to introduce items that COuld not be taken after he had relinguished his office as Chairman. These concerned the two Officers not seeking re-election, John Frid and Joe Crewe. He went on to evalute the services of these officers to the Association and thanked them for their dedication and the Work that they had carried out on the Association's behalf. He then reminded Members that there was provision made in the Articles of our Association for special reCognition of a member had giVen significant services. Th1S was, he said the granting of a FellOWShip an that to date had not been awarded. The Chairman said that he now proposed to remedy the situation and from the chair h , e proposed that John Frid, the Association's Honorary Secretary for the past ten years, be given that honour. ThiS was seconded and the Meeting carried the proposal unanimously.

John Frid then thanked the Members for their generous gesture and expressed the honour he felt at being elected the first Fellow of an Association that had been very much part of his life for longer than he cared to remember. The Chairman then concluded the special items by making presentations to John Frid and Joe Crewe as a token of the Association's thanks for their loyal services.

Mr. Frid and Mr. Crewe thanked members for their gifts.

Sa Election of Chairman

Mr. John Frid (Cambridgeshire County Council) was nominated and elected Chairman for the ensuing year.

The new Chairman thanked the Members for this further honour, and said that he hoped his year of office would be of benefit to the new Officers shortly to be elected by the meeting. He said that he had seen many good and efficient men occupying the Clair in the Association, and that he hoped that his year would not detract from the previous high standards. He felt that every Chairman should set himself a particular task during his term, and he had decided that what efforts and time he could make available would be directed towards strengthening Branch activities as these were he felt, the grass roots and strength of the Association.

Sb Election of Vice Chairman

I t was· agreed to leave this office vacant.

Sc Election of Secretary

Mr. Eric Brown was nominated and elected to this office for the ensuing year.

Sd Election of Treasurer

Mr. C.T. Peacock was nominated and elected to this office for the ensuing year.

Se Election of Editor

Mr. J.A. Thompson was nominated and elected to this office for the ensuing year.

Election of Liaison Officer and Legal Advisor

It was agreed to 'leave these offices vacant.

8h Election of Auditor

Mr. E. Foster was nominated and elected to office for the ensuing year.

9. Election of Council

Ashort discussion was held prior to the election of council. Some members felt that there was no need for a Council but others felt it was necessary and that they should meet in an effort to lead the Association forward.

The following members were then elected to Council:

Mr. B. Lowe Bedfordshire

Mr. Riley West Glamorgan

Mr. Smith Humberside

Mr. Kitchen Humberside

10. The Honorary Treasurer put forward the motion "That, if, in the opinion of the Council of the AsSOCiation, it becomes necessary to increase membership subscriptions in 1980 an increase of up to £1.00 on all such subscriptions shall be implemented from January 1980." This was carried by the meeting.

11. The Honorary Treasurer put forward the motion "that the following persons, being members Who have in the past made considerable contributions to this ASSOCiation be considered for election as Honorary Members of the Association, R.P. Holdway, B. W. C. Thacker and D. HalL"

This was unanimously carried by the meeting.

Mr. Holdway being present at the meeting, thanked members for this honour. He went on to say that the ASSOCiation had much to offer and it must go forward if it is to surVive.

12. Any other BUSiness

a) The Chairman said that his project for the year would be the Branches. He was partiCUlarly concerned wi th the S.E. Branch. A discussion followed and it was agreed that the Chairman would try to reSolve the disappointing performance of the S.E. Branch.

b) The question of qualification of Branch Membership was. raised. It was explained that Branch Members should be Members of the Association, but persons not be discouraged from attend1ng meetings.

The Chairman opened the afternoon session b introducting Dr. Jeacocke a member of Health and Safety Executive responsible for conveyance.

Dr. Jeacocke said that he was very leased to be invited to attend this :eeting particularly as John Frid had retired as secretary and he could ersonally say a few words of praise the way he had carried ou this office.

Dr. Jeacocke went on to say that he was concerned with conveyance of dangerous substances in this country and was also associ ated with the International field. Over the ars conveyance had become more ye I involved particular g01ng into the E.E.C. It was 1mportant that we in this country should be active in the international field because if a regulation was adopted in the E.E.C. it should be right for all.

Dr. Jeacocke concluded his talk by answering general questions, the main ones being

a) What sort of quantity of dangerous goods coming from abroad? This varies from port to port but keep in mind that 2% to 3% of vehicles on the road are tankers.

b) Is the traditional role of local authority enforcement Changin ? Difficult to answer, it may W:II be that in the future this will change.

c) Are we in the throws of the first step of removal of enforcement by the local authority?

The whole question is wide open.

Mr. Holdaway proposed a vote of thankS to Dr. Jeacocke.

There being no further business the Chairman closed the meeting.

PROCEEDINGS

Unattended Tanker

On 11th July, 1979 before the Gravesend Magistrates a tanker driver, Ur. L.R. King, of Chatham, Kent, pleaded guilty to a breach of Regulation 7(1) of the Petroleum Spirit (Conveyance by Toad) Regulations, 1957.

Evidence was given that the driver was aware of the requirements of the Regulations and that the vehicle was unattended for some 25 minutes. The vehicle was parked in a residential road and it contained 22,000 litres of aviation fuel at the time.

A fine of £50. with £10. costs was imposed.

Conveyance by Road

On 15th November, 1979, Farmair Limited of Staplehurst, Kent pleaded guilty to three charges before the Folkestone

The offences related to the carriage of thirty 45 gallon drums of AVGAS on a vehicle which did not comply with the Conveyance by Road Regulations.

The offences were as follows:-

(a) No fire extinguisher (Reg.6 of 1957 Regulations)

(b) No fire shield (Para.1(c) of 1st Schedule of 1957 Regulations)

(c) No flame symbol (Reg.4(1) of 1971 Regulations)

Fines of £50., £100. and £200. respectively were imposed with £50. costs.

Breach of Licence Condition

Mr. D.W.H. Lee of Newenden, Kent pleaded guilty before the Ashford (Kent) Justices on 29th November, 1979 of keeping a greater quantity of petrol than that permitted by his licence.

The Magistrates heard that the defendant (the licensee) had used a tank which had not been approved or tested for storage _ having previously been 1n Use for d' 1 I 44 1ese. n consequence, some 40 gallons of petrol was being kept 1nstead of the 4000 gallons permitted by the licence.

The licensee was fined £20. and ordered to pay £20. costs.

Un1icenced Storage

Two partners trading as Coachwork Renovations were prosecuted before the Gravesend on 12th December, 1979. Mr. G.S. Smith and Mr. R. Ashenden each pleaded guilty to keeping petroleum mixtures without a licence.

A previous licence for the storage of paints and thinners had expired, and despi te repeated letters and visits a new licence was not taken out some two months later.

The Justices imposed fines of £50. on each partner and costs of £50. were awarded ag ainst each.

Licence Contraventions

A petrol filling station proprietor was fined a total of £1,150 with £100 costs at Thames Magistrates' Court for four infringements of the licence. On appeal at Snaresbrooke County Court the convictions were upheld but the fines were reduced to a total of £290. Costs were not affected.

Defective filling Opening Caps

A major oil company was fined £100 with £10 costs at West Central Petty Sessions for each of three contraventions of Regulation 12(2) of the Petroleum Spirit (Conveyance by Road) Regulations. The caps of the filling openings to three compartments of a tank wagon were found to be unlocked and insecurely closed.

Wrong delivery

When calling at a filling station an inspector noticed the contents of an ground diesel oil tank being transferred into a tank wagon. He was informed that a mixed load of petrol and diesel oil had been delivered two days previously. The petrol had been safely transferred into the underground tanks without incident. The driver then moved the tank wagon to the above-ground tank and delivered 5000 litres of petrol into it by mistake. He then tried to transfer 5000 litres of diesel oil into the tank. The overfill came out of the tank ventilating pipe. Fortunately, the aboveground .tank was bonded.

Because °of mitigating circumstances, such as a recent road traffic accident and personal problems, the driver was let off with a caution for contravening No. 16(7) of the Petroleum Spirits (Conveyance by Road) Regulations. For failing to notify the Council of the incident the licensee was cautioned for infringement of the licencee.

BASEEFA

CENELECSTANDARDS

Despite various articles in the technical press, there still seems to be some confusion, among both manufacturers and users, as to the implications of the adoption of CENELEC Standards EN 50 014 to EN 50 020, which were published at the end of 1977 as BS 5501 : Parts 1 to 7.

The standards have been agreed by 15 CENELEC countries, listed in the front of each standard. Framework Directive No 76/117 EEC of 18 December 1975 made legislation provision whereby any electrical equipment constructed, tested and certified by an approved body in accordance with harmonised standards, which have now been specified in Specific Directive No 79/196 EEC of 6 February 1979, would be legally acceptable in any EEC country, as if it had been tested and certified in that country. BASEEFA is the approved UK body for the certification of electrical equipment for use in flammable atmospheres for industries other than mining.

The specific directive will not become !egallyenforcible before 6 August 1980, I.e. 18 months after its adoption. In the period prior to this however it is expected that there will be voluntary acceptance of equipment certified to the CENELEC standards other than the country of ongm.

Several of the countries that have agreed the standards, including UK, are already accepting equipment for certification to the harmonised standards. It is anticipated that manufacturers an eye to the European market wdl have new products certified to these standards, and will apply for re-certification for any other products they think might find a market abroad.

The framework directive is however an directive, to ' which It IS permissible for production for domestic use to existing national standards to continue. Other countries may accept equipment made to these standards, on a VOluntary basis.

The rules of CENELEC require that countries that have accepted the harmonsied standards should withdraw conflicting national standards after a suitable transition period. Several suggested 10 years as a SUitable penod, but this has not yet been agreed. This means that each country will continue to certify to its existing national standards as well as to CENELEC standards for some time to come.

There is no suggestion that the adoption ot a new standard implies any deficiency in the old national standard. The harmonised standards are simply a

means of increasing the area of marketability of certain products. It is not a safety requirement that apparatus should satisfy the new standards as soon as they appear; indeed, it is unlikely that manufacturers would be able to supply apparatus to the new standards until some time after publication. Also, since equipment supplied to national standards should be acceptable to the legislative authorities for the period of its useful safe life, there would seem to be nothing to be gained by the user's insisting on ordering to the new standards.

There are certain factors with which manufacturers should be familiar with regard to what can and what cannot be accepted under these new standards.

In order to be fully acceptable for the issue of a certificate of conformity all component parts must be to the appropriate harmonised standard. It will thus not be acceptable in the certification of a new motor to incorporate a terminal box which was previously certified to a non harmomsed standard. Components which do not comply with the relevant harmon!sed standards and it has been agreed ID thIS respect that sintered discs do not comply with the flameproof standard, could not for the present be included in a certificate of conformity. It would however be possible in this latter context to cover this by an inspection certificate but this involves the circulation of the certificate by the certifying authority dealing with the new application, to all other approved bodies (i.e. the other European certifying who h.ave the right to object. This process IDvolves a statutory four month period during which such objections may be made.

Marking of apparatus

The BASEEFA Ex Memo, which gives details of BASEEFA markings, is being reVised to take account of the changes brought about b the adoption of BS 5501 Parts 1 t% 7 (CELENEC Standards EN 50 014 to 020). The revised Ex Memo should be available later this year.

In the meantime required marking details are given in BS 5501 Part 1: (EN 50 014) supplemented by requirements in other parts of thiS standard.

Some of the new markings are already appearing on certificates, even when equipment has not been certified to the new standards. For instance, it has been BASEEFA practice in the past to mark certificates that specify special conditions of use with the letter B, added to the certificate number: in the new marking system X denotes special conditions of use.

The suffix /B was also formerly used in intrinsically safe certificates for all 100

intrinsically safe and associated electrical apparatus to denote a requirement that a system certificate was required. This is no longer a requirement of ne,,: and the practice has been dlscontmued.

Certificates for 'associated electrical apparatus' to be used in conjunction with intrinsically safe apparatus have previously been identified by the letter S, added to the certificate number.

BS 5501 Part 7 (1977) (EN 50 020) requires that associated electrical apparatus should be denoted by the symbol (E Ex ia) or (E Ex ib).

BASEEFA has adopted this marking but during the changeover period ' some certificates may even carry both the S and the bracketed symbol.

Anomalies are inevitable during a changeover from one marking syst to another, particularly Where has b.ee.n started under the old system and IS IDcomplete when the new system is adopted.

The revised Ex Memo shOUld cl .fy the situation until the new Systean established. m IS