00 per annum

Emergency Procedures

H. T. E. Jackson, Senior Petroleum Officer, Greater London Council.

We all know that petrol is dangerous material and spend our time trying to minimise the risks by safe methods of construction and soon. No precaution however is foolproof and there ,comes a time when petrol escapes from the safe location and then we have a condition of emergency.

There are all sorts of emergencies to which a petroleum officer may be called. I recall cases ranging from 40,000 gallons 'Of aviation fuel on the surface of a lake to a complaint 'Of fumes which 'turned out to be due 'to a lady's rather generous use of her nail v'arnish! I cannot cover all types in one paper and propose to deal mainly with leakages and sp'illages at filling stations and similar installations which are 'the most 'common 'Occurrences.

To give an idea of the risk that may occur, let us consider the following examples. A room of 10 feet by 8 feet by 7 feet high will be made fully explosive by the vapour from two pints of petrol. The same room will be made fully toxic by ,one 'tenth of this amount, that is by four fluid ounces. In the absence 'Of air currents to 'cause dispersion portions of the room could be 'fully explosive or toxic by even smaner quantities. The power of an explosion of such a volume could theoretically throw a largish car some 10 miles.

Now the title of this paper sounds neat and tidy and suggests perhaps that a code can be laid down .for the necessary 'actions. This however is far from the case and emergencies 'seem to show new facets every time, and the best one can do is to lay down general principles to be followed with great emphasis on the need to be ready for the unexpected and not to jump to conclusions however similar the case may seem to be with previous ones.

I think we can make a rough division between two types of incidents. Firstly where notification is made by the person keeping petrol of a leak or suspected leak and secondly the case where notification is received from other persons complaining of petrol or petrol odour ,in their premises. Now in !the first case ·if ,there is not already other physical evidence of leakage it is just as well to spend a little time in ,checking that there has in fact been a leakage. In some cases quite a quick check has disclosed that the supposed leak was in fact only a piece 'Of bad arithmetic. I remember one case where the first message was that a 'tank had leaked 900 gallons uvernight, but after a few questions on how mten 'the tank had been dipped and so on, it became clear that the loss could in fact have occurred over a period of three years and in fact eventua:l tests showed that the installation was sound and that the loss was due to normal running losses over the whole of this period. This was private installation and I think this sort '()If mistake is more likely to happen 'in that type rather than on filling stations where record keeping, although far from ideal, tends to be somewhat more detailed. As well as bad arithmetic there are other things which can give rise to mistakes in quantities in tanks. For example, clogged vents will give rise to high readings on the dipstick just after a tank waggon delivery and low readings after the tank has been in use. Water in a 'tank, if it becomes high enough to cover the bottom of the dip pipe will also give rise to faulty readings. High vent pipes are another cause of innaccurate readings due to the varying weight of the petrol vapour in the vent pipe.

Now these first enquiries should give some idea of the general picture involved, that ,is whether the loss has been a large sudden loss in recent time or whether ,it has been a ,comparatively small seepage over a period uf days, weeks or even months. It is important to get this idea as to what has been going on 'as it must colour one's judgement on the priorities for the next moves. If it is clear that ·there has been a large loss recently then there ,is 'a possibility of it turning up in the near future in some dangerous area and therefore a high priority for checking and warning nearby premises. As an example there <was one case where 500 gallons were lost into the soil due to a tank waggon delivering into a disconnected offset fiU pipe. Now it was quite clear that 'there had been this large recent loss and the priority was to check nearby premises and warn of the danger. In actual fact it was found ,that a seepage had 'already started into the basement boiler house of a block of flats next door to the premises. The boilers were automatic and unattended, and had they not been put out at once there would almost certainly have been a major explosion within an hour or less. In fact half an hour after the boilers had been put out neat petrol was running through the wall of the boiler ho.use at a rate of some five gallons an hour. I think that thiS case emphasises the need for prompt action in cases <Yf this nature.

The most Iikely places that a seepage will reach are basements, G.P.O. ducts-which are very prone-cellars, railway tunnels, sewers and similar underground spaces. There are however also less likely places in which petrol does sometimes turn up. It can climb up' walls by capillary action where damp courses are broken and give rise to contamination in ground floors. An premises cYi these types near to the 'occurrence should be vis'ilted to check whether any contamination has started and to warn occupiers of the possibility of it starting later so that they may recognise it give notification as soon as it starts. It is surprising that, If not warned, people will notice smells 'and do nothing about it for some hours or days-they may think it a smell of gas or onions being peeled or all sO'rts of strange things .they will not send notification until perhaps the situatIOn has got really dangerous-usually in 'the middle of the night or a weekend. So ,aUhough one does not wish to start a panic it is necessary to give warning to Drainage and other similar author1ties whose installations may become involved.

Now. to come to >the matter of remedial action. Well, the first thing obviously 'is to stop any further leakage or outflow. Sometimes it is not clear from which part of an installation the leakage has occurred and until this has been estabHshed from records or by tests it is not possible to stop any more loss unless the circumstances are sufficiently

serious to put the whole installation out 'Of use and have all tank contents uplifted at once. In a recent case spirit was seeping into a railway tunnel and although the actual quantity involved was not Iarge the risk was considerable. The nearby filling station which was the most likely source of .the seepage had no records available to indicate whether or not it was the source and ,the owners were therefore required to have all spirit uplifted at once. Following this, tests were applied and one <tank was found to be faulty (as a matter of interest this tank was only seven years old). In other cases where the leakage is n'Ot turning up in a dangerous position, or is not likely to do so, it may be possible to test the instaUation section by section without sterilising the whole. There is a useful quick check that can be made on suction lines which, whilst not necessarily positive in all cases, can be often a helpful indication of a possibly leaking line which can then be put out of action pending proper pressure teslling. This test is done by holding the hose nozzle in a suitable container with ·the valve held fully open. The pump is then switched on and spirit should issue from the nozzle ,at once. If there is any delay in the commencement of flow it indicates that ,time has been taken to prime the suction line and this can only be due to either the line having been partly emptied by leakage or by leakage back into the 'tank past the check valve. In practice the check valves seem to hold pretty satis'factorily and the odds are on the delay being due ,to a leak. Now this testIs obviously more critical as the length of time that the pump has been out of use -increases. If the pump has been used just before the test ,there will not have been 'time for enough petrol to have leaked out of the Hne for 'a notice·able delay to occur (unless of course the line has a whopping great hole in it). This ,test will not work on Avery Hardol or Beck pumps. Examination of petrol records will often give an indication as to what part 'Of the installation is at fault. In this respeot I would like to mention that ,there 'is nothing magical about the figure of 1 % which is often quoted as the maximum working loss. With a pump giving over measure to the figure allowed by Weights and Measures Regulations on re-examination the loss would be greater than this. On the other hand, if a tank and its associated pump have heen working for some time 'at a figure of say 0.3%and then start to show a loss of say 0.6% it would obviously be suspect aI,though still well bel cm 1 %. Remedial action for premises which are being contaminated by seepage depends a lot on the type of premises and the degree of danger ,to them. l'f just a slight seepage is occurring, say to the basement of a building, giving rise ·to some 'slight degree of vapour contamination, then good ventilation of the area concerned and ,the removal ·of any possible -igniting sources such as electrical equipment, gas appliances and so on, may be suffioient. Frequent inspections see that conditions are not worsening and also warnmg of any occupants of the building of the steps they should take to avoid risk would also be necessary. Remember that in 'addition to fire and 'explosIon T'isks there is also a very definite toxic risk from much 10wer concentrations. Any concentration suffi'oient to give an explosimeter reading should be treated with care and a reading of 10% or more of the lower explosive limit will indicate fully toxic conditions. I have known cases of people who have noticed smells of petrol in their premises but have not reported ·tt at once and they have clearly been suffering from headaches without reaHsing that these were resulting from the smells.

If liquid petrol is reaching a basement or similar space action will have to be ,taken to remove it as far as possible.

Lf 'the seepage is not large it may be possible t'O mop it up with sand or to leave sand where it will abs'Orb the seepage as it 'occurs and then to remove it for drying 'Off in some safe area. If -the spirit is collecting in a sump 'Or manhole or similar space it will usually be possible to ladle or syphon it off -into suitable containers. One way of dealing with smaU skims of petrol floa'ting on water in manholes, etc., is to emulsify It with some form of detergent. Household detergents such as Om-o and 'industrial detergents like Slix or Teepol work quite satisfactorily. The emulsification makes it easier ,to rem'Ove .the bulk of the spirit with the water and any ,that is left behind will vapourise less quickly. If the quantity 'Of spirit involved is not large it may be reas'Onable to flush ,the emulsion down any available drain.

Sometimes when the flow 'Of spirit into premises Is large, or the premises are particularly vulnerable due to their usage, it may be necessary to rtry and recover the spirit before it can reach ,them. This can be done by digging pits or trenches outside basement walls or by digging them near the source 'of leakage. I menNoned previously a case where spirit was getting through the wall 'Of a basement boiler hoU'se. Had this seepage been ,all-owed to continue the bO'iler house would have been out of use for months and the occupation of the flaots 'Over would have been hazardous. A trial pit was therefore dug outsIde the boiler house wall and the bulk of the spIrit laying in the soil was recovered from this pit. When these sort 'Of w'Orks have to he caI'l"ied out it is important to remember rthe precautions to safeguard the workmen doing them. Breathing ·apparatus may be necessary if they are working in excavations or forced ventilation and, 'Of course, all possible precautions 'against making sparks while drilling or digging. In 'some cases it may also be desirable for workmen to wear safety harness in case ,they 'are 'Overcome in the exoavation.

In deep manholes and similar spaces it may not be possible to ventilate sufficiently to reduce vapour concentration below explosive -limits. A measure of safety 'On a temporary basis may be achieved by putting dry ice, that is CO2, in ·the space where it will form CO2 gas which 'is heavy and will tend to stay in the manhole with the spirit vapour and it will inhibit or make ignition much less likely. It also has the advantage of being a very cold material and it wiH cool the spirit 'and make vaporisation less. It will not, of course, reduce the toxic hazard and in an enclosed space wiU add to this risk ·since it is an asphyx'iating gas. The quantity of dry 'ice needed 'is one pound for every eight cubic feet 'Of vapour space and safety will not be achieved until dry ice has vaporised.

Now we come to the second type of situation where a complaint originates from 'Someone with petrol or smell of petrol ,in their basement, tunnel or what have you. If only odour is present the first job may well be to decide if in f.act 'it arises from petrol or is due to a gas leak or other cause. The nose is a pretty good guide but no by any means infallible, particularly 'as old petrol can change its smell quite a lot and can come to resemble diesel or have a smell which whilst unlike :fresh petrol is quite typical and I can only describe it as "stale petrol". The MSA explosimeter can help ,to differentiate between petrol and town gas by use of the carbon filter and 'there are other meters which

also achieve this. Gas engineers usually have meters which will establish positively if a smell ,is town gas. If liquid seepage is present it may well be easier to come to a conclusion since to smell can be added 'appearance, volatility and flammability of which quick checks can be made. On a longer term basis, laboratory anaIysis of the liquid be useful. A point to be watched is that petrol can qUIckly change its colour 'and ,odour if it comes in contact with bitumen 'Or tar damp-courses,cable wrappings and suchlike. It will also darken considerably with aging in the soil. A rough guess as to its age can sometimes be made if it has been laying on the surface of water. Where there ,is a petrol/ water interf.ace certain fungi grow and these can be seen as streamers hanging from the interface. Their growth is something in the order 'Of one eigth of an inch per year.

The firs't priority will obviously be to s;afeguard the premises concerned and the same remedial measures I have already outlined will be applicable.

The next step, and this can offer many snares and delusions, ,is to find the source of the trouble. It will clearly be logical to start with the most likely source which will be the nearest storage to the contaminated premises-and uphill oOf it W there is any local gradient. So, if there is a filling station next door to the complaint this would be the place to start investigations but do not be convinced straight away that it must be the source. There have been several cases where the source was found to be other than the likely one and I woOuld like to give you a few examples.

There was one where a hotel located on a hill had vapour contamination in its basement. At the top of the hill was a filling station-the logical suspect- and .this was investigated very thoroughly without disclosing anything except some his'tory of minor sp'illages. The smell in the hotel continued and finaHy was found to be due to leakage from a faulty suction line 'in a filling station located at the bottom of the hill. The soil of this hill was very fibrous leaf mould and acted asa wick. The petrol was travelling something like 500 feet horizontally and 100 feet upwards to reach the hotel basement.

In another case spirit appeared in a G.P.O. manhole over a long period. Although the quantities involved were not large, due to the enclosed nature 'Of the manhole, explosive concentmtions were common. Very close to the duct leading to the manhole-some three or four yards-was a filling station, clearly the prime suspect, and everything possible was done to rule out any leakage from this station. The seepage into the manhole continued however. Some four or five hundred feet away and slightly downhill of the manhole were two other installations which did not show any undue losses in their records. When one of these installations was put 'out 'Of use due to the occupiers moving away, the coOnditions in the manhole quickly improved and although this case has not yet been finally proved it seems extremely likely that the further 'installation was the culprit.

Another ,incident involved the basement of a house in a heavily built-up neighbourhood where intermittent smells of petrol occurred. There were no storages in the immediate vicinity but the nearest ones were investigated, as were local drains, lock-up garages and every such poss'ible source.

The smells continued however and finally investigation of very old maps oOf the district disclosed that a small watercourse originally flowed over a site which is now a filling station and at which there had been a known leakage of 300 gallons of petI:Ol some three years before. The distance between the two premises was about three miles. It appeared clear that some of the loss had gradually seeped down the run 'Of the old buried watercourse to give rise to the trouble. There ,was not much that could be done in this case except keep a watch on the vap'our concentration in the basement until it finally cleared itself.

Complaints often arise from petrol getting into sewers either by spills getting 'into gullies wbich are not ,intercepted or by leakages into the ground seeping through faults in drain pipes or sewers. Now obviously any liquid petrol will ffow down with the water in ,the sewer, but many sewers are warm and under such 'Conditions there may well be a fl'Ow of 'air upwards aga'inst the fall of the drain, and petrol vapour may therefore travel upwards with the 'air. Such a case happened recently where smells of petrol in the drains of a hospital were found to originate from petrol leaking into 'the sewer hundreds of yards away and well downhill of the hospital.

These examples will serve to show that tracing the source of a compJ<aint is anything but straightforward, but once the source has been found 'the acNons already discussed concerning stopping further leakage and so on will apply.

Now I have been talking on the practical aspect of leaks and emergencies and the works which are necessary. One question which may be in your minds is "What powers?" As far as work on licensed premises are concerned the matter is pretty straightforward. The Association's Code recommends a Hcence condition which requires the licensee to take such steps and do such works as are necessary. I do not think however that such a condition 'Could be held to cover works that are necessary 'off the licensed premises, but it is often possible to persuade the licensee or his petrol company to do such works if they are convinced that the fault lays with 'their installation. If dangerous conditions exist 'in other people's premises ,it is clearly a moral duty to advise and persuade them to take the necessary steps or to allow the licensee's or petrol company's workmen to do it for them. There 'is, however, no power to make them do sO nor is there any power of entry into their premises to see if dangerous conditions exist. Fortunately it is nearly always the case that all concemed are anxious foOr safety and prepared to take any advice 'offered. It ,is perhaps worth bearing ,in mind the pOSSIbility of civil litigation for expenses or damages 'Occasioned by a leak 'and therefore t'O be somewhat guarded in comments to people other than the licensees. One may well be convinced of the source of a leak but without positive proof ,it would be unwise to make any statement as to its source or responsibility f'Or

It.

Help from Fire Brigade or Police may sometoimes be necessary. Conditions may be such that Fire Brig,ade standby against a possible 'ignj.tion is desirable or if roads need to be closed or the public diverted away from danger the Police will do ,this. It will usually be found that these authorities will look to the Petroleum Officer to advise on the scope and na'ture of the precautions necessary. Als'O on this matter of help from dthers it is as well ,to always have readily available the phone numbers of 'Other authorities, petrol companies and so on who may be needed jnan emergency. They will usually also be prepared to supply emergency numbers for use out of normal working hours.

Emergency Procedures

(For incidents involving Petroleum Spirit or other Flammable Liquids)

1. PREAMBLE

It will be appreciated that no notes or information can be sufficiently comprehensive to cover all types 'Of emergencies. These notes are intended to provide helpful advice and concise information dn brief, general form as an aide-memoir ,to members faced with a major emergency; the notes 'are not in chronological order.

ASSESSMENT if time permits, the situation should be carefully asses'sed; jumping to premature conclusions can lose vital time. It is :hardly necessary ,to advise that act:ion should err on the side of oaution and ,it must be emphasised that emergencies do not run true to form or always follow the pattern of known similar incidents.

RESPONSmILlTY for a particular incident will vary; in aB cases, however, cO-'ordination of the division of responsibility ,is vi-tal. Normally control will rest wi,th the following: Fire ·Brigade (fire control, fire prevention),

Police (traffic and crowd control), Petroleum Inspector (technical 'advice and co-ordination of all services, Oil

Company (technical advice, provision of equipment, uplif.ting spirit, etc.)

POLLUTION - all River Authorities will be concerned with pollution of surface water, sewers and water at any level. Any degree of poHution should be avoided if at al'l possible. Where pollution has already occurred, or is totally unavoidable, every effort must be made to contain the pollutant fQr ultimate disposal.

2. PRELIMINARY MEETING

The purpose of a meeting -is to ensure 'that all persons and authorities (e.g. listed below) likely to be involved in an emergency involving petroleum spirit (or other highly inflammable matedal) are adequately informed with regard to ,the possibilities of an emergency and what action, advice, equipment and facUities are available -to deal with any such emergency.

Petroleum Inspector

Police

Fire Service

Engineer's Department-8urveyor Sewage Works Manager Highways Superintendent Drainage Authority

River Board Oil Company and other appropriate representatives from industry G.P.O. Gas Board List 'Of Emergency Telephone Numbers Electricity Board British Railways (where 'appropriate) 3. SUGGESTED ITEMS OF EQUIPMENT

Explosimeter

Gully Emptiers and Sewer Equipment

Sewer Maps

Emulsifiers

Portable Lighting

Notices "Danger-No Smoking" etc.

Materials for Roping off Hazardous Areas

Pumping Equipment

Petroleum Installation Maps

4. CHECK LISTS FOR PARTICULAR INCIDENTS

Alert all Services

Leakage of Spirit Stop leakage where posSIble Check sitocks, quantities and reported olosses involved Uplift sp'iri,t if necessary Check all nearby premises Check for aB sources of ignition Check for explosive and toxic concentrations Damaged Road Tanker Dam and uplift spirit If in sewers flush thoroughly Notices Road blocks, and exclude un-essential vehicles from danger area. Check !for all sources of ignition. Check for explosive 'and toxic risk.

5. DISPOSAL OF SPILLED SPIRIT " Containment by dams of sand, earth, straw, etc.

Uplift.

Subject to decision rflush drains, either with, or followed immediately ,with emulsifier.

Pollution, booms of rope, net, or t·imbers between banks banks or craft.

Produced by The Association for Petroleum and Explosives Administration.

Portable Hovv to

Fire Extinguishers: Choose

There are 'several factors to consider in selecting the right kind of portable extin'guis'hers for any premises but the most important is the kind of fire for which they are likely ,to be required. Other considemtions which the buyer of extinguishers should bear in mind are :

Method of Operation All installed on one premises (or in a group of companies) should, where possible, operate by 'the same method. For example, where water and :foam extinguishers are provided it will avoid confusion if all the extinguishers operate in the 'upright' position.

Operating Angle of Jet Extinguishers may be required to fight a fire where ,the jet has ,to be directed below the level 'Of the iheight of the extinguisher (e.g. under floorboards) or upwards (e.g. iinto fume hoods) and 01'0 meet such requirements extinguishers fitted with hose are needed.

Effective Range Where the approach to a fire may be restricted (for example in the case ,of a fire overhead in a I'Of.ty room) the range of extinguishers is importJant.

Shape of Jet A spray is more suitable than a jet where a fairly 'large area has to Ibe {lovered and where the penetrati:on of a soJoid jet is not needed. Purely surface fires in ordinary solid combustible materials are more effectively dealt with by a spray. A few water are fitted with dualpurpose nozzles designed to emi't either a jet or spray.

Ease of Handling Some extinguishers may be too heavy or cumbersome for women OT elderly persons t'O use. In such instances smaller sized extinguishers should be installed.

Maintenance Some 'require more maintenance than others and where there ,is a choice ,between extinguishers of similar type, equally suitable ,in other respects, the user may wish t'O install the type needing less maintenance.

Environment High or low temperature (above 43°C and below 4°C) may have a detrimental effect on some extinguishers. Care must be taken to -choose extinguishers which will not prove dangerous or damaging 'in certa'in situations - e.g. having a If'oam extinguisher near a heat treatment bath, 'or a water extinguisher 'in a 'computer room.

GENERAL PROTECTION Fires in Ordinary Combustible Materials Water The effectiveness of an extinguishing agent on fires in ordinary solid combustible materials (e.g. wood, paper, textile fabrics) depends principally upon its cooling action. Water has better cooling properties than other agents and is best for use on fires in ,these materials which may ,re-ignite if not adequately cooled. Also, water can penetrate readily to reach a deep-seated fire.

Some Limitations Water is a conductor of electricity and must not be used on live electrical equipment.

,SPECIAL RISKS Fires In Flammable Liquids Dry Powder Dry powder is generally the hest type of extinguiS'her for dealing with fires in flammable liquids. By extinguishing the flames 'over ;the liquid, dry powder acts more rapidly rthan foam 'and 18 particularly 'Suitable for deaHng with fires which may spread to surrounding materials before a complete foam blanket could be formed over the burning liquid. These extinguishers deal more effeotively with large areas. of burning liquid than 'other extinguishers 'Of comparable size. They 'are effective too on fires !in free-flowing liquids especially where the tJiquid spills and spreads 'Over a fairly large area. Dry powder is a non-conductor of electricity and can safely be used on fires where there is a risk of electric shock.

Some Limitations The cooling properties of dry powder are limited 'and it gives no protection against re-ignitron which may occur a:ftter application ceases. It is not as effective as foam 'On fires in liquid containers where ,the Uquid 'has overheated either because it has been burning for some time or because it has been heated in a process.

Foam Foam extinguishes a fire by forming a blanket on ,the 'Surface of a burning liquid. The foam bIanket remains in position for sufficient time ,to prevent re-ignition and t'O allow the to cool. Foam extingu'ishers are, therefore, especially SUitable f'or dealing with fires in which a liquid has been burning for 'Some time or because it was being heated in a process. Examples 'include: oil quench tanks; oil fired boilers (where a sill is provided), linseed boilers, and varnish keto ties.

Some Limitations It is difficult to form a blanket 'Of foam on a free-flowing Uquid and quite 'impossible to do 'so when the liquid is flowing over a vertical sooace. Liquids spilled on the floor or other horizontaI surfaces may spread over a ,larger area than normal discharge ,from a f'Oam extingu'is'her can cover. A large number 'Of liquids such asalcohols, break down the foam produced by an 'Ordinary portable extinguisher and prevent the formation 'Of an effective blanket. Foam is a conductor 'Of electricity and should not be used on live electrical equipment.

Carbon Dioxide Carbon dioxide, by extinguishing the flames over the liquid, acts more rapidly than foam and is more suitable 'ror dealing with fires which may spread to surrounding materials before a complete foam blanket can be formed over the burning liquid. Carbon dioxide extinguishers 'are suitable foor deal'ing with small fires involving escaping liquids on bath horizontal and vertical surfaces. Use CO, extingu'ishers where the overriding factor is to avoid damage or contamination by dry powder or foam. Examples of risks where ,they are especially suitable 'include: coating and spreading machines, kitchen ,ranges, delicate labratory equipment. Non-conductor of electricity. Some Limitations Theco'Oling properties of carbon dioxide are limited and it gives no protection against which may 'Occur after application ceases. It is not as effective as foam on fires 'in l'iquids incorrtainers where the liquid has overheated either because it has been burning for some time or because it has been heated in a process.

Vapourizing Liquid Vapourizing liquids, by extinguishing the names over the liquid, act rapidly, but because extinguishers containing these agents are comparatively small they are useful only on very small fires in flammable liquids. Chief application is in dealing with fires in petrol ,and oil-driven engines. Nonconductor of electricity. Some Limitations Should not be used or kept in confined spaces or any place where there is a risk that someone may 'inhale the vapours or the products formed when the vapours are heated by fire. Methyl bromide is highly toxic and not recommended. Fires Involving Electrical and Electronic Equipment Carbon Dioxide Dry Powder Vapourizing Liquid These three agents are most suitable for dealing with fires involving electrical equipment. Where live electrical equipment may be involved extinguishes containing water or foam (which are conductors of electricity) should not be used, because 'Of the risk of shock. Where, however, it is possible to cut 'Off the current, water, which 1sthe most efficient extinguishing agent for these fires, can be used, unless oil 'or other flammable liquids are involved, in which case the fires should be treated as a flammable liquid fire.

Carbon dioxide extinguishers are most suitable for dealing with fires involving electronic equipment, in view 'Of its delicate nature.

Note: Extinguishers should conform with British Standards and be approved by ,the Fire Offices' Committee. The Home Office has recommended to fire authorities that they should in future adV'ise against the use of C.T.C. in vapourizing liquid extinguishers.

With acknowledgement to the Fire Protection Association.

Is Pre-Payment due for an Upsurge?

Up to now pre-payment self-service has ?eveloped sl?wly and has been used mainly at selected SItes where lIkely demand for or night sales have made :it an economic and indeed an attractive proposition for securing business that otherwise would be lost. But after this pel'iod of proving and of probe into its 'it is. now beIi:eved that the pre-payment system I.S on t?e pomt of moving into wider use on a 24-hour baSIS, pavmg the way for unmanned 'robot' stations

This we understand, is ,the view of those maj'Or petrol who have shown the. most interest ,in prepayment, and it is certainly the vIew of De La Rue Instruments Ltd.

De La Rue Instruments, 'a technical off-shoot of the De La Rue organisation's banknote printing division, has been concerned for some years in the manufacture of both automated cash dispensing equipment for banks and automatic note counting units, and the experience led ,to the acquisition of the import rights of the Ardac note-acceptor unit developed in ,the United States and which has been ,the basis of pre-payment equipment used by service stations in the UK.

Now a further move by De La Rue has been to acquIre the sole distribution rights in the UK for the Swedish-made Autotank unit which provides a fully automated pre-payment system with £1 note and 50p coin acceptors. This has been done after considerable study and assessment of the petrol retailing situation in ,this country. 'First of all', PhiIip N. Davis, De La Rue's marketing development manager, told Service Station, 'we set out to establish credibility for pre-payment. We 'looked at it and could see no good reason why petrol should not be sold on a pre-payment system as opposed 'to a post-payment system. 'Continental methods tended to support our own thinking on this. For example, in Scandanavia almost 60 per cent of the petrol sold through self-service systems is sold on a prepayment basis, and we could see no reason why a simHar percentage should not be reached in ,this country. 'The petrol companies, indeed, had also been realising that post-payment self-service is not the only means of selling petrol in this country', Mr. Davis continued. 'They had come to the basic marketing decision ;for one very good reason: post-payment itself 'is a system which costs a lot of money, 'and, like everything else, has to be cost-justified. 'In the very early days of post-payment, sites converted to this system saw an enormous 'increase in throughput and in some instances douhled or even quadrupled ,their sales. And it became not uncommon to see the half-million and then .the million-gallonage mark per annum.'

Reimbursement But obviously, Mr. Davis said, if one went on {!onverting sites indefinitely there would just not ·be suffioient petrol sold to 'allow 'reimbursement to :those who had made the considerable ,capital 'outlay to convert their sites. kbout two years ago the petrol companies had been rapidly coming to the conclusion that some of ;the 'later post-payment sites were not seeing such substantial uplifts in gallonagebecause there were other similarly equiped competitors not far away. Struggling Sites Mr. Davis believes that for economic reasons oil companies are crying 'halt' to any large-s·cale of ment, and except in 'the large conurbatlOns and towns, WIll be turning more and more to the pre-payment system. In some cases this policy would avoid the need rror clos'ing down struggling sites.

As it is, Mr. Davis estimates ;that from about 32,600 sl'tes about five years ago we are now down to about 29,350.

One development visualrised is for a group of smaller sites to be put on a pre-payment unattended basis, with one man in charge of the group.

This has been the general thinking in the petrol 'industry recently, as De La Rue s'ees it, although the company is first to admit that the current thinking is ,something 'that can be influenced and changed almost day by day.

But with the present omens in favour of a greater use of pre-payment, De La Rue is well posit'ioned to serve development and are geared up to supply acceptor umts suitable not only for the one-pump link but also for the 'robot site' situation where one unit can be linked to up to four pumps.

Credibility The company believes ;that one ()If the reasons why ment never got 'Off .the ground initially was insuffiCIent credibility for ;the system. In rthe main has been fairly easy to obtain the necessary seals of appr·oval,although fire 'Officers dn some ,areas have been opposed to the system.

Generally speaking, 'says Mr. Davi'S, there has not ,been sufficient documentallion and dissem1nation of 'information throughout the country a!bout pre-payment, but now much of the objection ,caused by pure ignorance :is being swept away. De La Rue, in fact, aims to ,consolidatecredibHity for the system, not only with the petrol ·companies and the trade generally but with .the motoring public. 'There is still a hang-up between the motor,ist and a prepayment system', said Mr. Davis, ' ·and we have to a certain amount of mistrust that he If·eels about puttmg money dnto any kind of machine.'

Women's Influence This seems to apply more in the case ()If male motorists, for according to .a ,survey 'conducted by BP and quoted Iby Mr, Davis, more women than men preferred to use ,this type of machine. One notable reason 'appea'l"s to be rfuat ,women are used to reading instruction ,cards - as, rfor instance, to programme ,automatic washing ma-chines and other domestic machines -and are quite happy to get out of the car and foHow the instructions on forecourt equipment. In Tact it was probably the women who made self-service equipment successful.

But on the post-payment system, Mr. Davis 'believes the oil companies did their sums wrongly in ·reation to ,the sale of TBA. They made it part of the policy to put up ,splendid accessory shops, but had ·been finding that cus·tomers going into .the 'accessory shops to pay rfor their petrol were spending 15 minutes :there looking round, because many motorists were f.asoinated by ,the ·accoutrements of motoring. But in the meantime their 'cars were holding up valuable space by the petrol pumps, and to cap it 'all they weren't aotuaHy buying anything ,in the 113A shop anyway.

All of <this, Mr. Davis believes, is now weighting itself against the post-payment method of selling petrol in this oountry. 'Now, we're talking about pre-payment as a system, not in ,terms of spending £55,000, as on post-payment, hut an average 'Of £5,000 top weight - and that includes the :installation of the equipment, the >linking .to the pumps, and 'if necessary, the purchase of two new pumps.' Two Versions The system .is available in two versions, one the UnifiU for controlling rfrom one to ,three pumps, and the Multifill for two to rfour pumps. When the Unifill is connected to more than one pump, only ;the pump selected by the customer at that time can be used, whereas with Multifill the next customer can enter his money and use another pump as soon as the first has removed the nozzle from his pump.

The customer can 'insert £1 notes or 50p coins up to the value of £3, the present limit under the Home Office Model Code, and this is safeguarded by interlocks in the unit which prevent the acceptance of further notes or coins. A 5-digit non-resettable counter is fitted ins.jde the oonsole on which takings are recorded.

As also required by the Home Office Model Code, the petrol supply is cut off automatically three minutes ofter first lifting the nozzle or operating the nozzle lever and any remaining credit is ,cancelled.

The console, 'installed alongside the pump or pumps, is an attractively styled unit and has the feature of a shaped acrylic panel providing overhead protection for the operating panel. The sequence of operations listed on the front panel is as follows: (a) A 'green illuminated button indicates that money may be inserted; (b) insert money .to required value; (c) press the green button; (d) go to the selected pump and follow instructions, and (e) replace the nozzle.

During normal operation the only attention required by the service station operator is switching in and out of prepayment by means of a key-operated switch on ,the console and clearence of 'the money box. A diagnostic panel with light bulbs simplifies fault-finding if a service call is required.

Reprinted with acknowledgement to Service Station.

Sale of Explosives

All users 'Of explosives including gunpowder, detonators of all types, capped ;fuses and safety fuse, exept Government Departments and holders of storage accommodat:ion licensed as Magazines by the Secretary 'of State, must have a Police Certificate or a Police Licence covering 'their purchases of explosives and accessories. The seIler must ensure that the appropriate document is held before supplying explosives or accessories.

Co-operation between ,the purchaser and supplier is essential, as each has his sepamte legal responsibilities.

A Police Certificate is required for the purchase of high explosives, detonators of all types (plain, electric and delay) capped fuses and 'Cordtex'.

A Police Licence lis required for the purchase of blasting powder (gunpowder) and safety fuse. . The essential principle of Police Certificates or Police Licences covering the purchase and sales of explosives and accessories is that 'the person or firm to whom ,they are granted must Ibe 'in the opinion of ,the Chief Officer of Police a 'fit' person or firm to keep the explosives in questi'On. 'IS no definition of 'fitness' either in the Explosives Act or 'ID 'any Order in Council made under it, but H.M. Inspector of Explosives considers that 'One of the conditions of a Police Certifica,te ()r Polke Licence is that the Chief Constabel must be satisfied that the applicant will take such precautions as will afford all necessary security for public s-afety.

may asked why Hcencees 'Of Magaz'ines do not need Pohce or Police Licences ,to cover their purchas. es. The answer 'IS that, while 'the Secretary of State has power to refuse a Magazine Liicence, there is no power Explosives Acts 1875 and 1923 to refuse thfl regl5'tratl'On. 'Of premises and the local 'authority has no to 'Wlt?hold a store licence provided the appropriate ?OndrtlOns laid down are complied with. The Police CertIficates and Police Licences are necessary, therefore (exept where the 'intending user is the licencee of a Magazine), to prevent undesirable persons having access ;to explosives and accessories.

Wherever possible, the Police Certificate or Licence should run concurrently in date with ,the user's Store licence or registration of premises. Generally speaking, Police C.ertificates and Licences covering the purchase of explos'lVe& and acces'S'Ories are current for twelve months. If the storage licence can be given a similar life, and both documents carry the same date,the work of renewal as it affects the local authority and the essential checking which falls 'On the seller are greatly simplified.

Exploslves for 'Immedlate Use' Where explosives are required for immediate use, the, Chief Officer of Police may issue an 'Immediate Use' certIficate or licence to authorise the ac::),uisition of larger quantities .of explosives 'and detinators than can be acquired under 'Private Use'. These certificates cover 'one transaction only, and must be countersigned by ,the supplier at the time of sale.

The following opinion, expressed by H,M. of Explosives, is of considerable value in interpretmg the phrase 'immediate use'. "The linterpretation of 'for immediate use' used Sale 'Of Explosives Order 1928 (O.C. No. 28) 'is difficult, as I't is recognised that explosives cannot always be used. up immediately after receipt. If kept for however short a period, explosives must be put in a safe place, secure from entry. It is probable that local authorities would raise no objection, incases where keeping of expI()sives for, some delay must say, -three or four 'occur, to .the days, but .1': a longer period is found to be necessary the local authorities should be consulted with a view to registering It or licencing the places of keeping, if the local authorities consider it necessary" .

Local Authority Responsibilities in the Storage and Transport of Petroleum

Over a hundred years ago, in 1862 the first law was passed fur the safe keeping of petroleum', 'so although the motor car was not at ·the time a part of the everyday scene, the danger from petrol and other such products was already well appreciated. What this old Act did was simple enough - it regulated all vessels carrying petroleum so that when they entered harbour they conformed strictly to :the harbour rules about their plare of mooring. It also provided that not more than 40 gallons of petroleum could be kept within 50 yards of a dwelling house and gave search powers to enforcement officers. This was just 1;he beginning, and since that time there have been amending Acts and revising Acts until today we have the 1928 Act which brought everything in line with (what was then) modem requirements.

Why Regulate? This 1928 Act, ,caUed Petroleum Consolidation, forms today the basis of petroleum law in relation to safe storage and transportation. The need for these laws shows to everyone the highly dangerous nature Oof petrol; but even now this is not appreciated as it should be. Some think that petrol is unnecessarily rigidly controlled and will gleefully tell tales of ,throwing lighted matches into buckets of petrol, and - nothing happened. Lucky for them. Petrol is a sophisticated super fuel, designed after all to bum fiercely in ,certain 'conditions. These 'conditions are artificiaily and cleverly created in the internal combustion engine, and the design is such that the petrol just can nat avoid exploding inside the cylinder. The unfortunate thing about ,this is that these conditions can be and are created accidentally - and then all 'that is needed is the presence of 'a source of ign,vtion. The foolhardy gentlemen with the bucket just do not know how much of a gamble they take - but ,the right combination of petrol and air might have rendered them in no position to tell the story aiiterwards.

Obviously then petrol handling and storage had :to be responsibly controlled, and the 1928 Act as amended made this the responsibility of the London County Council, District Councils and ,the City of London's common council. *

And How? The way the control is exercised is by licens1ng, and the first Section of the Act makes it an offence in generaji tOo keep petroleum spirit without a licence granted by the Local Authority. There are of course minor exceptions,namely small quantities kept in 'certain conditions for either sale or private use. Obviously 'it would be unnecessary and difficult to regulate the keeping of all small quantities of petroleum spirit, and this is the reason for the exemptions, allowed when cel'tain 'storage conditions are maintained.

The work which the Act imposed on local authorities is carried 'out by their local Petroleum Officers. Sometimes these are full time offici'als, but often the work forms part of the other duties of weights and measures (trading standards officers) or fire prevention officers. Usually the allocation of the work is left to the local authority Itself to arrange most suitably.

The authority can, through its 'officers, impose whatever it considers necessary upon those keeping petroleum spmt, but foreseeing great differences 'in attitudes at local level the Home Office has brought out a Model Code ?f Conditions. These are advisory only, and a Iocal authorlty d'Oes have to 'adopt them. 'Sensibly though, most do, and the WIser authority varies little from what ,the Model Code says. From time to time, however, progress moves faster than the iTevision of the 'Code and then it might be unnecessary for additional requirements to be 'included in a licence.

The vast majority of petroleum officers look upon those Model out. Codes as 'their working bible, and know them inside

There are five main ,types of storage which concern ,the local authority. T'here are the large distributing depots, often keeping ,hundreds of thousands of gallons the roadside filling stations, Where a modern one will up to twenty thousand gallons; the mixture store in the hundreds of gallons; ,the small metal bin perhaps licensed for about 50 gallons; and finally the newest (and perhaps the most troublesome) the underground car

Distributing Depots

Naturally 'the larger the amount of petrol stored 'the greater the and distributing depots present :the greatest potentIal danger. Fortunately, the 'Owners of these places are ·the most aware and most careful of all petrol storers, and a manager may know his particular problems better than the enforcement officer himself. ,F'irst of all these stores 'Construct.ed where possible wen away from 'Other hU'ildlOgS for reasons; and the day 'Will one day come when all stores which 'are badly positioned in built up areas WIll be gone. Safety precautions are extreme, and have to ,be. No matches, studdedi boots, or sm'Oking are allOWed :on the premises. All electrical equipment must be to ,the standards so that :the possibility of chance 'IgnItion :IS ruled 'out. At the same time construction and operation must be such ;that of dangerous .vapour does not take place - all valves, ,tanks, and fill pomts must Ibecompletely leak proof at all times. there be a burst tank or a fraoture 'Of any kind the wall must he sufficient to hold all the petrol WhICh IS lIkely t'O leak out. Obviously all construction within the depot must be of fire resisting material, and a good high fence must surround it .to keep 'Out vandals. First aid firefight!ng must be right up to scra!toh, and even grass and must be systematically cleared away in order to mlOImIse the spread of fire it 'it should break 'Out. If a distributing depot has one thing which ,takes the eye it Jis the large capacity tanks, hut the second thing becomes

apparent as 'One approaches the depot, and that 'is the preponderance of large red and white notices. "No Smoking", "No matches", and so on - a warning to all that beyond those notices lies danger.

The roadside filling station has become in the last 40 years as much a part of Hfe as the grocer'lS shop, and the regulation 'Of these usually f{)fms the bulk of a Local Authority's work. Consultation with the Authority begins at the planning stage when blueprints are sent to the petroleum officer for his approval. He will scrutinise them solely with safety 'in mind, planning being the responsibility nf another department. What does he look for? 'First, distance from any building and the public highway - the site must be such that if a fire should occur employees or users of adjacent buildings could get away, and accumulation of dangerous petrol vapour 'is unlikely. Normally the petrol storage tanks should be placed below ground in concrete or perhaps stra'igilt into non-corrosive soil. Their design, and that of all 'Other underground engineering fittings for that matter should be such as to retard corrosion. The officer will look to the position of ventilation pipes, see that there is room for the large tankers to refill without ,causing obstruction, and check that all drainage 'is through approved petrol interceptors. The problems of new sites out in the country are nowhere near so difficult as those of old established sites, where 'ideal installations are difficult to build.

Once the construction begins, the petroleum officer will be on s'ite at very regular 'intervals. He will usually pressure test the tanks before they go 'in, and personally supervise their Iowering into the ground. Where concrete is used to encase them, he will see that there is at least six inohes of it all the way round. When the fitters have laid all the pipe 'Work, he will also test that for leaks, and check that it is adequately protected against damage from the passage of heavy vehicles over it when the garage becomes operational. As the building progresses he will see that electrics are of a safe type, particlarly in and around the pumps themselves and in kiosks, and before opening day the place will be as safe as he can make it within the bounds of reasonableness. Evidence of his activities will be plenty, there will be notices warning of the hazards, some Author'ities requiring a large general "Petroleum Spirit, Highly Inflammable" notice where all users of the garage can see it, and others go further requiring a notice 'On each individual pump, fire extinguishers must be to hand, and kept ,in good and usable order .. Of course when all 'is new, licensees are aware of the petroleum officer and his needs, but when a filling station is long established and has run for twenty years or more, things are ,apt to get a little slack. This means that the 'Officer has ,to inspect regularly to keep licensees and their staffs on thek 'toes and a good one will do a 'thorough inspection at least once a year. He ,looks for defaced notices, talks to the staff and asks them, for example, Where the emergancy cut off switch is. If the attendant does not know, the officer will have a sharp word with the licensee. Worse still, access to the switch may be blocked by stores or rubbish, and this will justify an even sharper word. Another routine matter is to examine the labels on the fire extinguishers, which will tell him the date of the last inspection. It is Hkely that he will talk to the staff about the procedure when the tanker comes, and ask to examine the regulation certificate book. Vent pipes will come under his scrutiny, he will look ins'ide the manholes to check that the fill cap is screwed down and the right dipstick is in the right tank, and there has been no accumulation of dangerous 'ru'bbishor petrol soaked rags in the bottom.

Self Service A new development is the self service garage and this is of two kinds, 'attended' or 'unattended'. In the former there is usually a battery uf pumps on the usual kind of fo:ecourt and each one carries instructions which the motOrIst can read, and if he carries them uut he can serve himself with petrol. The amount is shown on the dial 'in the customary way and the price too - and when his delivery is <:omplete he wiU go to the control room where the payment IS made. This control room 'is the brain centre of the garage, and a new type 'Of garage girl with clean hands and a smart dress will sit at her console to control the operation of each pump separate'ly. She can switch it on or off at will, and can advise or instruct by loudspeaker. The amount of petrol s:rved and the price, 'is shown automatically on 'the console.m the office,and above all at the throw of a switoh she can Isolate the whole forecourt in the event of a spillage or other dangerous incident.

Complete self-service is not the same. This usually works like any other automatic machine, with a place to accept pound notes or coins, 'in return for which a properly predetermined amount of fuel is delivered upon correct operation of the pump's nozzle.

These places have :their own special hazards. There is always an element of risk in allowing. petrol dispensers to be handled by unskilled people, but thiS has been up to and in the main overcome by engineering ,ingenUIty and acceptance of the problem as ,Lt rs. Before a petroleum will licence such a store certain features oOf are insisted upon. For example, there must be a bUIlt-m cu out to make sure that dispensing of fuel takes pJoace only when the nozzle points downwards as in the tank of a car, and it wiU have dragon's 'teeth oOn .the underside prevent it faIling out with careless handling. himself and drive away with the nozzle In Ins. I must be made that the nozzle shears og'a:fely WIth 'a minimum of spillage - and ,the pump does not get pulled over. Obviously the latch type nozzle would not .be on that kind of installation and it demands speCial attentIOn to fire-fighting apparatus. It 'is usual a comph:tely self ice installation to have an extingUIsher behmd glass, in some instances the . breakmg th I of· e g ass ·11 WI automatlcally actuate a fire alarm and call the brigade.

So the supervision of the roadside filling station is a very important part of the petroleum offi.cer's and the responsibility for its safety Hes heaVily on hiS shoulders.

The Mixture Store In considering variety in the work of the petroleum officer, it may well be that he has almost as many mixture s.tores as filling stations. These 'Mixture Stores' are places for the keepinaof petroleum mixtures ,that come with m th legal In general, these are every bit as as petrol, and are usually for products like cellulose pamt and thinners,