The Bulletin – February 1977

B U L L

Journal of the Association for Petroleum and Explosives Administration

Bulletin

Talking point ...... ·· ................. 21 Notes and News 22

Current Legislation 23

An Exercise in Care ···· 28

Tanker Accident at Audley End 32

Electrical Apparatus for Explosive Atmospheres 33

Hon Secretary's Notes 34

The Price of Petrol The Safety Angle 35

Legal Proceedings 37

The Testing of New Existing Petroleum Spirit Storage Tanks 38

' Branch Reports 42

Hundreds of Oil Tankers May Risk Explosion , 44 Technical Corner .45

Hazardous Incident at Erdington 46

Talking Point

There is a growing tendency, in these days of rising inflation, for some Petrol Stations which do not produce the required level of profit to be closed down by their owners, usually large Petrol Companies, until a time of greater financial stability.

The length of time during which they will remain closed cannot be assessed initially, and as they are usually relatively modern sites, complying with our present Codes of Practice, they present a new variation on the old theme of which method of making safe the Petroleum should ask for.

Clearly, slurry-filling is out of the question, as this would render the tanks useless. Waterfilling is a possibility, but if the period of disuse continues beyond a few months, the fabric of the tank will become damaged by the water. Some Fire Authorities require that the suction line and fill pipe be closed off, usually by covering with sand, with a light concrete screed above, but this method alsO has its opponents.

Clearly, some guidance to Petroleum Officers on A National level is necessary so that a uniform standard of "making safe" emerges throughout the County.

HONORARY

notes and news

PARISH COUNCIL FIGHTS UNDERGROUND PETROL TANKS

Underground petrol storage tanks belong in a industrial district not in the Botley Conservation area, the local Parish Council was told when it considered a planning application recently.

A local company sought permission to install the tanks in the conservation area, but members of the council expressed concern about bringing more inflammable material into the area, preferring to see them in an industrial situation. It was agreed that more tanks would increase traffic and danger. The original application had been granted on condition that the containers were screened by trees, and this had not been done. It was suggested that all planning permission granted was "conditional," that the conditions were not enforced and that this was where planning fell down The council agreed, therefore, to object to the application for the underground tanks.

PORTSMOUTH GARAGE UNSAFE FOR PETROL SALE

The Secretary of State for Employment has agreed with Hampshire County Council that the premises of Car Exchange in Tangier Road, Copnor, are unsafe for the storage and sale of petrolo

Hampshire County Council refused to grant a petroleum licence for the premises which have been a garage for 40 years.

Proprietor,Hr R oW.H. Ottley appealed against the refusal and a public inquiry into the appeal was heard in April of last year.

As a result the Secretary of State has announced his de'cision that the appeal should be disallowed, and that the premises should not be issued with a petroleum licence.

The Inspector for the Health and Safety Executive, Dr Cecil Johnson said in his report to the Secretary of State after the inquiry there were six main areas of hazard connected with the premises o

These were that the position of the road tanker stand was hazardous to people in the building if a fire broke o ut; that petrol could find its way into the public sewerage system if there was a spillage ; pedestrians could pass clOse enough to be a possible source of starting a fi r e; the position of the pumps could cause hazardous petrol fumes to fill the showrooms; an y f ire at the pumps could spread into the

showroom through glass windows; and that there was a particularly bad risk to people in the living accommodation above and adjoining the premises.

At the inquiry, Hro Ottley proposed alterations which he said would bring the premises up to the required standards but the inspector decided that these would on{y make "marginal improvements."

In his conclusion he said that he was unable to visualize the filling station being capable of being brought up to a standard acceptable for licensing purposes, and he recommended that the appeal should be dismissed o

'POISON PERIL' ALERT IN THE CAR PARK

Multi-storey car parks can be POison traps, a shock report warned recently.

Deadly carbon monoxide gas from car exhausts can build up to many times the thresh-hold level recommended by safety experts.

to

Staff in some cash kiosks are exp osed nine times the normally permitted I eVel carbon monox1de and eight times the lead particles in the air. level of of

The report comes from Dr. Malcolm Fox of the Leicester Polytechnic School of Chemistry and environmental health Officer Mr. Ivor Barker.

The result of their survey of several car parks in England is reported in the journal of the Royal Society of Health

They are urging the Government t '. o lns' on monitoring systems to trigger alar 1St the levels rise too high. ms When

The researchers say the maJ'or b' Id cause Of pollut10n 1S a U1 -up of cars wait . t . th . lng at the eX1 W1 eng1nes running.

The alarm system would light up signs warning motorists to switch Off.

BOY, 14, HURT IN PETROL BLAST

A boy of 14 was hospitalised home with his clothes smoulderin petrol exploded in his face g

after crawlin after a g can of

The accident happended wh J en ohn Dabo Church Street, Bury, was colI t. , of ec 1ng wood fr a derel1ct house ln nearb y Wash L om " ane for a bonflre It lS thought John wa , s upstalrs wh someone threw a match into the en room The can exploded and John was blown down th t· out into the st reet, e s alrs and

CURRENT LEGISLATION

by E. FURNISS, B oAo ,IL LT SoA o , Assistant County Consumer Protection Kent County Council Officer

Over five years ago a list of current petrolelOO legislation was published in the Bulletin. Since then we have seen our Association extend it's field of interest t . 1 o lnc ude matters relating to explosives.

During that time also there has been the of the existing statutory provlsl0ns with the Health and Safety at Work etc. Act 1974 for better or for Worse.

With these changes in mind therefore I . glve below an updated list which may Useful to other members. In addition lt is hoped that it will ensure the accuracy and completion of the list should anyone point out any errors or omissions.

EXPLOSIVES

Explosives Act 1875 (Chapter 17) Orders in Council Nos. 1,lA and IB Classification of explosives

Orders in Council Nos. 2 and 2A Factories other than gunpower. Orders in Council Nos 3 and 3A Magazines

Orders in Council Nos. 4 and 4A Small firework factories

Order in Council No.5 GUnpower stores

Orders in Council Nos.6, 6A and 6D Stores for mixed explosives. Order in Council No 9 Sale of explosive

Orders in Council Nos . 10 and lOA Import of explosive

Order in Council No. 11 Notice of accidents

Order in Council No. 12 Private use

Order in Council No 13 Small arm nitro-compnund

Order in Council No 15 _ Fireworks of sulphur and chlorates

Order in Council Nos. 16 , 16A and 16B _ Registered premises

Order in Council No. 19 of phosphorus and chlorates

Order in Council No. 26 Picric acid

Order in Council No. 27 Di-nitro-phenol

Order in Council No o 28 Sale of explosive

Order in Council No. 29 Liquid oxygen

Order in Council No. 30Pcetylene

Order of Secretary of State No. Floating magazines gunpower

Order of Secretary of State No.

1 2 and Floating magazines other explosives 2A

Order of Secretary of State No. 5 and 5A Compressed acetylene with gas oil

Order of Secretary of State Nos o 7, 7A and 7B Packing of explosives

Order of Secretary of State No 9 Compressed acetylene in porous substance Order of Secretary of State No o 10 Young persons in danger buildings

Order of Secretary of State No. 11, llA, llC, and lID

Conveyance of explosives Explosives Act 1923 (Chapter 17)

Compressed Acetylene Order 1947 (No. 805)

Packing of Explosive for Conveyance Rules 1949 (No 0 798)

Packing of Explosive for Conveyance Rules 1951 (No. 868)

Conveyance of Explosives Byelaws 1951 (No. 869)

Stores for Explosives Order 1951 (No. 1163) Magazine for Explosive Order 1951 (No. 1164) Fireworks Act 1951 (Chapter 58)

Stores for Explosives Order 1953 (No. 1197)

Emergency Laws (Miscellaneous Provisions) Act 1953 (Chapter 47)

Control of Explosives Order 1953 (No. 1598)

Control of Explosives Order 1954 (No 757)

Conveyance of Explosives By el a ws 1958 (No 230)

Keeping of Firewo r ks Or d er 1 9 5 9 (N o . 1 3 11)

Explosives (Conveyance) (Private Railways)

Byelaws 1960 (No. 1347)

Fireworks Act 1964 (Chapter 23)

Ammonium Nitrate Hixtures Exemption Order 1967 (No 1485)

Explosives Acts 1875 ' and 1923 etc o (Repeals and Regulations 1974 (No 1885)

Explosives Acts 1875 and 1923 etc (Repeals and Modifications) (Amendment) Regulations 1974 (No. 2166)

Explosives (Age of Purchase etc o) Act 1976 (Chapter 26)

GASES

Petroleum (Compressed Gases) Order 1930 ( No. 34)

Gas Cylinder (Conveyance) Regulations 1931 (No 679)

Compressed Gas Cylinder (Fuel for Motor Ve hicles) Regulations 1940 (No. 2009)

Gas Cy linder (Conveyance) Re g ulations 1947 ( No 1594)

P e troleum (Liquid Methane) Order 1957 (No 859)

Gas Cy linder (Conveyance) Regulations 1959 (N o. 1919)

":N F L AMMA BLE LIQUIDS

Petroleum (Consolidation) Act 1928 (Chapter 3 2 )

Petrole u m Spirit ( Mo t or Vehi c les etC Regu l ati ons 1929 ( No. 952)

Petro l e um ( Mi x ture s ) Order 1929 ( No 993)

Pe tr o l e um ( Transfer of Lic e nces) Act 1936 (Ch ap te r 27 )

P etrole um (Inflrunmable Liquid s and other Da n gero u s Substan ces ) Ord e r 1947 (No. 14 4 3)

Petro l eum Spirit (Con v e ya nc e by Road) Re g ul ation s 19 5 7 ( No. 191)

Petro l e u m (Carbo n Di su lphid e ) Order 195 8 (No 257)

Carb o n Disulphide (C o n v e y anc e b y Ro a d) Regulations 19 5 8 ( No 31 3 )

Petroleu m Sp iri t (C o n vey anc e b y Road)

Regulati ons ' 19 58 (No 962 )

Ca r bon Di sulphid e ( Co n v eyance by Road) Regulation s 19 6 2 ( No o 2 527)

Petro l e um Spi r i t ( Co n ve y ance b y Road)

(Amendment ) Re gul ati ons 1 9 66 ( No 1190)

Petroleum (Carb on Dis ul p h ide ) Or d e r 196 8 (No 571)

Petrole u m (I n f l a mm ab l e Liqui d s) Ord er 1971 (No 1040)

Inflammable Liquids (Conveyance b y Roa d) Regulatio ns 1971 (No. 1 061)

Inflammable S u bstances (Conveyan ce by Road) (Labelling) Regulat i ons 1971 (No. 1 062)

Petro leum (Regulations) Acts 1 928 a n d 1 93 6 (Repeals and Modifications) Reg u latio n s 1974 (No. 1942)

INFLAMMABLE SOLIDS etc.

Celluloid and Cinematograph Film Act 1922 Petroleum (Carbide of Calcium) Order 1929 (No . 992)

Petroleum (Carbide of Calcium) Order 1947 (No 1443)

Celluloid and Cinematograph Film Act 1922 (Repeals and Modifications) Regulations 1974 (No. 1841)

OXIDISING SUBSTANCES

Petroleum (Organic Peroxides) Order 1973 (No. 1997)

Organic Pero x ides (Conveyance by Road) Regulations 1973 (No. 2221)

TOXIC SUBSTANCES

None

RADIOACTIVE SUBSTANCES

Radioactive Substances Act 1948 Radioactive Substances (Road Transport Workers) (Great Britain) Regulations 1970 P adio fl. ctive Subtances (Carriag e by Road) : (Great Britain) Regulations 1974 (Legislat d . h d" 11 un er ea genera y administered by the Police and is included here only for complet e ness)

CORROSIVE SUBSTANCES

Petroleum (Corrosive Substances) Order 1970 (No. 1945)

Corrosive Substances (Conveyance by Road) Regula t ions 1971 (No. 618)

Th e fees p a yable in respect of lice f d · nc e s and registr a tion s are oun the Hisc e ll an e ou s Fees ( Var iation) Order I nRR ( No 1 and (For e x plosives) the Mi s cell a neo 70) Us Fe ( Variation) Order 1970 ( No. 195 4 ) es

Sin ce Januar y 1 9 75 the abOve le g ' has b e en af f ected b y Orders and Re g'ul t on a made under or by the Health d an Safet at Work e tc Act 1974 0 These inc1ud e :_ y

Health and Safet y at etc. Ac t 1974 (Commen ceme nt NOol) Ord er 1974 ( No. 1439) Health and S a f e t y at etc Act 197 4 No 0 3 ) Or der 19 75 ( No . 13 6 4)

Indust r ial Tribun a l s (Imp r o ve me nt a nd Prohibi t i o n Not i ce s App eals) Reg ul at i o ns 19 74 ( No 19 25 )

Hea lt h a nd s aie t y Lice nsin g Ap pe a l s ( Hea ring Pr o cedu re) Rul e s 1 9 74 ( No . 20 4 0)

A number of other pieces of legislation may nlso affect the work of the inspector and these are included below :

Pipelines Act 1962

Pipe-lines Act 1962 (Repeals and Modifications) Regulations 1 974 (No. 1986)

Highly Flammable Liquids and Liquified Petroleum Gases Re g ulations 1972 (No. 917) Motor Vehicles (Construction and Use)

Regulations 1973 (No. 24) (Regulations 19 and 96 deal with the construction and the maintenance of petrol tanks on motor vehicles)

International Carriage of Dangerous Goods (Rear marking of Hotor Vehicles) Regulations 1975 (No. 2111)

(Permits the display of warning signs conforming to the A.D R Agreement)

DE LA RV AVTOTANK

PRE- PAYMENT PETROL VENDING INSTALLATION

The history of pre-payment petrol vending has been a rather chequered one. The major oil Companies' feelings towards it tend to be warm and cool alternately, but with increased labour

charges and overheads generally, pre-payment is here to stay. Indeed, the era of completely unmanned stations in certain areas has dawned and can be expected to develop.

P L Brook De La Rue Crosfield Limited

UNMANN ED ' ROBOT ' STATI ON CON TRO LLE D BY HILL VIEW GARAGE, HIGH STRE ET , BILLI NGSHURST, SUSS EX.

Pre-payment commenced as a night time service to reduce overheads, especially labour costs, durtng relatively quiet periods, but it is now actively promoted as a 24 hour service, available during holidays and as a quick service facility during heavy throughflow. This 24 hour facility first led to thoughts of the unmanned station, and though still experimental, a munber of such sites are being evaluated by many of the oil companies. Being unmanned, overheads are low, and competitively priced petrol can be offered, so attracting sales and justifying the retention of a site which would otherwise be unprofitable.

De La Rue were the last of the three major pre-payment suppliers to enter the market. Extensive market research in the early 1970's indicated that there was scope for a professionally organised marketing operation to obtain a significant share of the developing prepayment market providing that:-

(a) Equipment was reliable and built to a high standard Dr La Rue had available Autotank, which had been installed and operated in hundreds of sites in Europe. It complies with the requirements of an 6afe System as defined in BASEEFA Standard SFA 3012 : 1972 for Group llA (certificate No. EX 74159).

(b) a national servicing organisation was available to provide, in many instances, a 24 hour response to calls for assistance De La Rue already had eighty service engineers operating throughout the count " t " . th' ry maln alnlng elr range of cash handling equipment installed in banks, garages retail stores etc., ,

(c) a complete "package" was offered to potential purchasers, in particular th oil companies, covering SUPply of eqUi e _ ment and all related work. This was p considered necessary to simplify the task of installing a pre-payment system.

De La Rue always prefer to SUPply a " deal installatl0n because the standard of is known to be at a high level. This prot work f l ' b'l " t ects our reputatlon or re la 1 1 y, and ensur safety is given topmost priority. es that

The De La Rue Autotank Package Deal comprises:1. A full site meeting between gara / ' 1 ge proprletor 01 company representat. the local Petroleum Officer, De La 1ve , representative and the civil e . nglneer'Rue contractor's representative. Ing

Planning and licenSing applic t· a lons.

DE LA RUE AUT OTANK

..

Experience of petroleum installations and awareness by contractors personnel of the importance of adhering to safety standards are considered essential. De La Rue recommend Pullens of Wimborne, Dorset for civil engineering work. They are approved by the National Inspection Council for Electrical Installation Contracting, and have extensive knowledge of petroleum installations generally and pre-payment in particular

Both Pullens and De La Rue work closely with the local Petroleum Officer. At the site meeting, a survey is carried nu+ to establish the suitability of the site for a pre-payment installation and to obtain the Petroleum Officer's recommendations regarding work to carried out, for example the need for a petrol interceptor.

After approval of the quotation, the necessary local planning and licensing applications are submitted in the normal way, and when approvals are received, the civil engineering work and Autotank installation is carried out. When the installation is complete the Petroleum Officer can inspect the site to approve the work

At the end of the exercise he can be sure that thp site is a first class updated station.

The e n ' --gency cabinet inc.luded in the Pack a g e Deal is th e nobro No . l which fully meets specifi cation requirements and was first approved by the local Hampshire Fire Brigade. It is a glass fibre moulding with facilities for emergency telephone, fire extinguishers and lighting equipment.

Other pre-payment suppliers are now also offering a .package deal, for in the interests of efficiency and safety it is preferable that a lia i son be established between the various personnel involved in installations Oil company acceptance of this view is confirmed by recent large orders received by De La Rue for Autotank package deal installations.

The development of electronic pumps has introduced a new element into pre-payment vending. However, continued co-operation and liaison between pump manufacturers, prepayment suppliers, and Petroleum Officers soon intergrate this into the normal effic1ent s y stem of pre-payment installations.

ROBRO No. I EMERGENCY CAB INET, PRODUCED BY ROBRO, 16 BOTL EY ROAD, PARK GA TE, SOUTHAMP TON.

Smoke signals start of exercise

REGULAR EXERCISES and testing of procedures are an essential part of any effective safety organization. All the locations at which Esso carries on its business organize such events at regular and frequent intervals, but probably the most extensive and complex of them all is the annual joint exercise at Esso Refinery at Fawley. The aim of this is to test cooperation and communications between the Esso Emergency Services and the Hampshire Fire Brigade under operating conditiQns. A fire or other serious incident is simulated in part of the plant. In previous years details of the exact location and nature of the event have not been disclosed,so that the

• 09.00

• 09.01

initiated by Igmtion of oil drum flares. Action by Process Operator call to Communication s Control Centre via '999': "Fire Crude Battery Zone n."

Es so Em ergency Services respond: Shift Superintendent F ire Section Shift Engineer Security Division Medica l Departm ent ad vised.

• 09.03

Emergency Services begin to arrive: their task will be to brin g into operation: 3 Trailer Mounted Monitors

I Monitor elevated on an 'AlIen' Crane

E ither Shift Sup erintendent or Station Officer (Esso F ire Brigade) will tran smit message to Communications Control Centre: "Fire on Cr ude Battery is Category n. Request Hampshire Fire Brigade to send three fire engines direct to fire and t hree to stand-by at Esso Fire Station."

emergency services are faced with an unpredictable situation but on this occasion the exercise was slightly different in it was designed to test previously agreed procedures

An essential part of the operation is the 'critique session' at which a video recording of the event is shown This, together with the feedback from the official observers who take part in the debriefing, is used for evaluation of the response and its timing, so that organization and equipment can be even further improved if necessary. The provisional timetable prepared for these observers gives an impression of the scope of the exercise.

bring in the Forward Control Unit (Red COntr I) and establish it just inside the access way to the e O of Central Oil Pump House. ast

• 09.45

• 09.50

Forward Control Unit ready to take over communi_ cations control.

After Forward Control established and as a resul of consultation between: t Duty Manager Plant Supervisor Fire Officer in charge

'Red Control' will be requested to call for 3 add't'110nal appliances.

One to proceed via Product Loading Pump H Ouse and report to Officer III charge on the north side i Old Jetty Road. n

Two to proceed via Propane Road and rePOrt to Officer III charge on the east side in Agitator R d These crews will used to bring 3 additional mounted momtors IlltO operation.

• 09.18

First Hamp shire Fire Brigade app li ances b egin to arrive. Officer in charge, after brief discussion with Shift Sup erintendent and Station Officer, will ass ist in bringing 4 additiona l trailer mounted monitors into opera tion.

• 10.40

• 10.45

(approximately) When Duty Manager and Se F ruor Ire Officer are satisfied that the Forward Control Unit is functioning satisfactorily, the exercise will be stopped

• 09.25

(a ppr oximate ly) Hampsh ire F ire Brigade /Esso will

Vi sitors, Ob servers, Hampshire Fire Brigade Officers in charge of operations and appliances, also Esso participants, will assem ble at the Administration Building foyer for debriefing session.

This article is reproduced by kind permiSSion of Esso Petroleum Company Limited.

Photographs by Dmitri Kasterine

Esso fire appliances arrive. The Shift Superintendent's car provides temporary forward control

Firemen manoeuvre monitors mobile high-pressure water nozzles off the lorrv that brought them

A hose is run out and connected to the nearest hydrant and a fireman signals 'Water on!'

The powerful waterjets provided by these monitors would make a hand-held hose uncontrollable. (Below) The refinery's Alien crane is adapted to take a monitor which tackles the 'fire' at a high level

The special/y-equipped For ward Control Unit arrives to take over communications at the scene of the 'fire'

TANKER ACCIDENT AT AUDLEY END

BY D.C. PRINCIPLE PEI' HOLEUM OFFI CE2 , COUNTY COUNCIL OF

On the morning of Tuesday, 5th October 1976, a petroleum tank wagon, conveying some 5,000 gallons of petroleum spirit was travelling along the All carriageway in the direction of Cambridge.

The 4 year old vehicle consisted of a tractor and 7-compartment tank wagon , of approved design. Five compartments were loaded with a total of 5,000 gallons of petroleum spirit, compartments Nos. 3 and 6 were empty.

The road at the scene of the accident is a 23ft wide carriageway, rising at a gentle incline and takes the course of an elongated " S". One side of the road is bordered by forestry and the other by a flint and stone wall boundary of National Trust parkland, there b e ing no buildings in the near vicinity. As the vehicle approached the top of the incline and wa s traversin g the right hand curve of the road , it appears to have 'jack-knifed' and skid ffiarks were evident from the nearside of the road across to the further side.

The road condition was dry; visibility good, and no other vehicle was involved in the accident. I t wo ul d s e em that the wheels of the tractor unit ma y have contacted the nearside kerb, and caused th e tra ct or to assum e a greater than normal angle to t he tank unit ; the momentum of the tanker unit t hen propelling the tracto r into a situation beyond

control, causing the tank section to roll onto its offside; career across and along the road, in this latter action, the front offside of No. 1 tank compartment was fractured by impact, thereby discharging the spirit into the roadway. The resulting vapour may have been drawn into the air intake of the engine or ignited via the exhaus t system qr friction sparks.

It can be seen from the photograph of the vehicle that the empty compartments 3 and 6 exploded, no trace was found of the manlids. The manlids to the five remaining compartments were intact and locked and the dip pipe covers were in position. As the tank unit had rolled over, the impact received by the dip cover attachments to the tank body had been sufficient to cause severe deformation, to have allowed escape of liquid and in the case of compartment No.4, the dip tube had punctured the bottom of the tank.

A quantity of spirit was removed from the damaged compartments (approximately 500 gallons) by road tanker and approximately 2 000 gallons of water / spirit was removed from areas by waste disposal vehicles.

The A.ll at the section was closed for some eight hours.

ELECTRICAL APPAP,ATUf) FOR EXPLOSIVE ATMOSPHERES FIRST PART OF HAJOP. CODE OF PRACTICE

Hany industrial processes use or produce gas, vapours, mists and dusts which are highly flammable and potentially, explosive o It makes sense to take great care whenever these are generated, processed, handled and stored , One vital precaution is to ' make sure any electrical apparatus in the area cannot produce arcs and sparks, frictional sparks or hot surfaces which could ignite the atmosphere, Peter Palles-Clark, chairman of the BSI committee resnonsible, describes the major revision of the code of practice for selection, installation and maintenance for electrical apparatus for use in explosive atmos- ' pheres, Reprinted from BSI News >

Many gases, vapours, mists and dusts used or produced in industrial processes are and potentially explosive.

Often electrical equipment has to be used in areas with such flammable atmospheres, and it is vital then that special precautions should be taken o An electrical arc or spark, a frictional spark even a hot surface may be all that is needed to set off an explosion "

Comprehensive guidance on the safe use of electrical apparatus in areas where such flammable meterials are generated, processed, handled or stored is to be contained in a new 12 part BS Code of for the selection, InstallatIon and maIntenance of electrical apparatus for use in potentially , atmospheres (other than mining apnl- explOSIve , . . ications or explosIve and manufacture), the first part of WhICh, Part 1 B' irements for all parts of the code, aSlC requ d has been publ ishe '

.!!.:!:.story

CP 1003, appeared in 1964

Its pr t 'onized the gUIdance avaIlable for and revolu 1 hO were requIred to meet regulation engineerS (Factories Act) Special 27 of the 1908 and 1944 , CP 1003 had just Regulatl'ons ,the first covered flameproof ana th arts ree p fety; the second, other techniques int· iC sa ( rlns. Division 1 now zone 1) are'as; and for use In plications for Division 2 (now zone the third, aPre the explosive substances are so 2) (Wh e areas on trol that a hazard is likely only well under c 1 conditions). Under abnorma

ode stood the test of time weIl o

The old c 't d'f' d I I r history 1 was mo 1 le on y nits 11 yehaese were changes made because of tWice, and t

The code was v er y widely ac ce pt e d metrication " here , and was also applied by many oth er countries Outside the U " K"

So why a new code of practice now?

There are several reasons 0 The past seven ye 'ars have seen many developments. Pending and actual modifications to safety legislation, changes in trading policy and the move towards breaking down technical barriers to international trade, the greater need for economic flexibility as well as technological advance, both in the U oK and internationally all have pointed to the need for a new approach,

To begin with there are now many more means of protection for electrical apparatus, The new code will cover nine protection meth0ds for dealing with the risk of explosi o n from electrical ignition sources " CP 1003 Covered just two certifiable methods and three other recognized methods, Logical structure

Each method of protection has its peculiarities and this has determined the structure of the new code o

The first part of the standard , now published, covers the basic requirements applicable to all methods of protection , and will thus be an essential reference document 0 Part 2 will be on classification of hazardous so it too will be used in conjunction with the other parts,

The various t y pes of pr otec tion will be dealt with separately in the follo w ing parts, Part 3 will be for t y pe of protection 'd' (flameproof enclosure);

Part 4, type 'i ' (i n t r insi c all y safe); Part 5, type 'p' (p re ssurizati on and continuous dilution) ; Part 6 t ype 'e' (inc rea sed safet y ) ; Pa rt 7, ty p e N; P art 8, type's' (special protection); and Part 9, types '0' and ' q ' (o il i mm ersed and s an d filled appa rat us , respectively) . Pa rt 10 will cover apparatus fo r use with combustible dusts ,

Part 11 another general information part will examples of specific indapplications, and Part 12 will cover the use of gas detectors.

Priority is being given to Parts 2 to 8 as these are particularly needed. Explorwork will begin soon on Parts 10 and 12 Parts 9 and 11 although important to .the , t overall balance of the code, are less urgen , and will take longer in preparation.

Scope of Part 1

Meanwhile, BS 5345 Part 1 contains much useful information of interest to all those concerned with explosive atmospheres. It lists the properties of many flammable gases, liquids and vapours, related to ignition temperatures and apparatus subgroups. One appendix includes a generally acceptable method of calculating flammability limits of mixtures of gases with air. Others COver degrees of protection against entry of liquids and solid materials, and the frictional sparking risks with light metals and their alloys.

Hon. Secretary's Notes

A letter has recently been received from the Health and Safety Executive in connection with the advice given last May by the Executive suggesting that there was doubt as to whether a breach of regulations made under Section 6 of the Petroleum (Consolidation) Act 1928 was an offence. Counsel's . . t've and Oplnlon has now been sought by the Execu 1 , it is his opinion that it is an offence under Section 33 (l)(c) of the Health and Safety at Work etc. Act 1974 to contravene any requirement and p rohibition contained in these requirements. The Ex ecutive thus feel that local authorities might now c o nsider it appropriate to institute proceedings for b r eaches of these regulations .

Part 1 also indicates the markinv,s to be found on apparatus certified abroad gives recommendations on tenance and testing, and marklng re q ulre. ments for certified apparatus. It contalns references to many related national, pean and International Standards to WhlCh apparatus now on the market may have been certifed Existing

installations

The new code of practice marks a major step forward but this do&s not mean, of course, that installations carried out to CP 1003 are at all unsafe. However, the new code should be of assistance to anyone buying replacement apparatus for an existing installation or attempting to modify one. It will show how the new technology may be compatible with the old through its reference to equipment made to newer standards like BS 4683 Electrical apparatus for explosive atmospheres, the parallel IEC publication 79 and the forthcoming European Standards EN 50 014 to EN 50 020.

(BS 5345 Part 1, price £4)

All members will by now have had the opportunity to compare the current format of the Bulletin with our previous productions. It would be difficult to argue that we had not lost some of the polish which we had previously accepted, but I feel that the present publication will serve Our purpose adequately during this time of financial restraint. In accepting this reduction in standard, and assuming that the present membership level will continue, means that we can once again return to a production rate of four editions per year, and this I feel would be every member's wish.

I would like every Member and Associate to feel that the Bulletin is a channel for his own thoughts, a means whereby he can air his views, discuss his problems or pass on information and advice which would benefit others .

The Honorary Editor would be more than pleased to hear from you on any subject of general interest, I should qualify that by saying that he will be selective in what he publishes so please let the dialogue recommence in 1977.

THE PRICE OF PETROL - THE SAFETY ANGLE

BY TO NY FL1NT'H fj j, S Jl. F2T Y CO-O :-:DIi JATO:: , TO'f J:.L CIL Glc J I' o;· 11'/,r;, LT D

Cost of petrol now completes with income tax on any list of "most unpopular" subjects. If this situation results in every drop of the precious stuff being carefully stored and used, there might be a welcome reduction in the other price of petrol. This is the average yearly bill of 11 dead and 70 injured as a result of accidents involving petrol.

Let's take a few examples, based on actual si tuations.

ACCIDENT "A"

Joe was safety-conscious. He knew that spilled oil and grease in the workshop meant slippery floors and the chance of a nasty fall. The inspection pit in particular got into a real mess in no time, so every day or so he'd sprinkle a good layer of sawdust into the pit to soak up the puddles. On this particular winter morning, a customer's car was towed in with the engine as dead as mutton. It didn't take Joe long to find the problem water in the fuel system. There was no doubt that the fuel lines and the tank would have to be completely drained out, so Joe got the car over the pit, climbed down and got cracking. As usual, the tank drain plug and the fuel line unions seemed to be rusted solid, but after some effort, a skinned knuckle and fruity comments to suit, Joe got everything slackened-off.

Petrol was dripping and splashing about during the operation, but that was normal on a tank job. Anyway, Joe had positioned the cut-down oil drum he kept handy for draining jobs, and he managed to get most of the petrol into that, and of course the sawdust took care of the rest. He was just starting to give the empty tank a good blow through with the compressed air line when there was a loud thump, a wave of searing heat, and everything around him was lit up by a brilliant orange glare.

Joe couldn't understand what was happening. He felt intense pain and couldn't get his breath. He dimly heard shouts above the roar of the flames His last sensation was one of horrified amazement that this could be happening to him.

The Result: Joe died as a result of his burns. The car was gutted and the wo r kshop and equipment badly damaged b y th e fi r e.

The Cause: A in the workshop. released from the

paraffin heater was burning As soon as petrol was fuel line and tank, it began to . evaporate, generating vapour. Petrol will do this as soon as it is exposed to the air, no matter how low the surrounding temperature may be. The petrol-soaked saw'dust and the open drum of petrol led to a rapid build-up of this vapour. Because petrol vapour is about three times as heavy as air, it will fill any low area such as an inspection pit, and then flow like water across the floor. The vapour reached the heater, ignited and flashed-back to the pit

The Moral: Don't drain fuel tanks or lines inside a building, and especially over an inspection pit. Heaters using open flame or electric elements are dangeroUs where inflammable liquids are handled or stored. Any material which will soak up fuels and oils should be cleaned up as soon as it becomes contaminated.

ACCIDENT "B"

Jack and Harry were safety-consciouS. They knew that it was dangerous to do any kind of hot work on a petrol tank unless it had been emptied and cleaned-out first. The lorry had been brought with a small leak on the fuel tank, which they decided could be cured by soldering. They got the tank off and emptied it without much trouble. They came up against the first problem Jack went to fetch the air line, thinking that a good blow through would clear any petrol vapour out of the tank. He found that the air compressor was " on the blink". Harry then remembered the oxygen cylinder on the oxy-acetylene welding set So they gave the tank a really good blow through with ox yg en

Still playing it safe , they decided to leave the tank for anothe r quarter o f an hour o r so Finally , Jack got cracking with the soldering itself. He ' d onl y been working on the leak fo r a minute o r two wh e n it happened!

Geo r g e, wh o had been wo r k i n g o v e r th e othe r side of the ya r d , wa s blo wn ov e r b y the bl a s t wav e. He s crambl ed unst ea d i l y to his f e et , hi s ears sin g in g fro m t h e

terrific bang. There was a cloud of dust and smoke, and he saw Jack and Harry lying sprawled about 10ft away from a grotesquely torn and twisted lump of metal sheet. George ran over, and stopped with his stomach heaving when he got a closer look at the mess his mates were in.

The Result: Jack and Harry were lucky they both survived their extensive injuries after long periods in hospital.

The Cause: It is virtually impossible to get rid of all traces of petrol and vapour by the methods Jack and Harry used. Any jOints, seams, or scale will trap, tiny quantities of petrol, which will generate enough vapour to blow the tank apart as soon as heat is applied. An ordinary soldering iron will provide quite enough heat to this. Oxygen is worse than air as a cleaning material anything that will burn or explode in air will do so much more Violently in an oxygen atmosphere. Cases of this happen every year, and people are killed or injured, even when the tank 01 dr um h as not contained petrol but stuff as a pp are ntly innoc e nt as diesel oil, lube oil, or even solid wax.

The Never do any sort of hot wo rk on a t ank, drum or Similar container u nl e ss it has been properly prepared first. The risks , and the proper precautions are e x p l ained in a booklet "Health and Safety at Work No 32 Repair of Drums and Small Tanks: Explosion and Fire Risks", produced by the Department of Employment, price 25p, direct from H.M.S.O. or through any good b oo kshop

ACCIDENT "C"

Young Jim was new to the job, and enjoying himself. The advertisement in t h e l ocal paper had asked for reliable people l ooking for spare cash as shift attendants on a service station. Jim was saving up f o r a motor bike , and when he found that the s er v ic e station boss was willing to let hi m do the Sunday morning forecourt shift, he was delighted, since that meant that he co u ld ca r ry on with his week-day paper r o u nd as well Anyway , the boss has shown hi m t h e ro pes , and he ' d soon got the hang o f t he p u mps , c ash reg i ste r , stamp machine and s o on The boss had also warned abou t bei ng careful because petrol was dangerou s s tu ff, as well as being too e x pe n sive t o s p la s h a r ou n d , so he had to wat ch o u t f or c ustomers smoking

On this particular Sunday, things were pretty quiet. It was cold and raw outside, and Jim was happy to sit in his little kiosk toasting his feet on the electric fire, and ocassionally rubbing the windows clear to make sure he didn't keep any customers waiting. A car pulled in, finally, and Jim went briskly into action.

"Fill her up should take about six gallons" mumbled the customer, and wound his window shut hastily. Jim had a bit of a job getting the pump spout into the tank, which had an awkward narrow fill opening low down on the wing. About halfway through the fill, there was a gurgling noise, and without further warning a jet of petrol shot out of the tank all over Jim's hand and down his overalls.

Being a sensible chap, Jim waited until the gurgling had stopped, and then managed to coax another gallon in by keeping the pump speed well down. He then replaced the pump nozzle and the filler cap, tapped on the driv e r' s window and announced that he'd only managed to get five gallons in.

A "fiver" appeared through the partly opened window and Jim went into the kiosk for change and stamps. He'd just opened the cash register when there was a soft whoofing noise and flames shot up his overalls. Jim staggered backwards out of the kiosk. He beat frantically at the flames and the flames to his hands and arm. leaped immediately He heard himself scre aml ng

The Result: Luckily, the motorist kept his head. He ripped off his coat, flung it around Jim, and pulled him to the ground, smothering the flames until they finally disappeared. Jim spent long and.painful weeks in hospital, and will carry h1s scars for the rest of his life.

The Cause: Jim had forgotten the electric fire in the kiosk. The petrol vapour from his splashed overalls immediately ignited when he went into the kiosk.

The Moral: Accident "A" demonstrated the dangers where naked flame or other ignition sources are allowed in areas where inflam_ mable liquid's are stored or handled. The other danger, often overlooked occurs when inflammable liquid is taken into a normally "safe" area, in an o pen container or in the shape of contaminated clothing. Open fires of any description hav e no place in kiOSks or rooms where this can happen , especially when they

are portable and placed at Iloor level. It is not even necessary for the victim to stand close to the heater tests have demonstrated that the vapour from one pint of petrol can be ignited up to 30It away from the spillage location. Nor is it necessary to have an obvious ignition risk like an open heater petrol accidents have been triggered by the spark caused when an ordinary electric plug is pulled from its socket.

The accidents described are not isolated events. The same casualties due to the same causes are repeated year after year. One thing, however, has changed. The heavy hand of the law is npw a lot heavier as a result of new penalties under the Health and Safety at Work Act.

Legal Proceedings

KENT

Conveyance Leaks on Tank Wagon

On 26th May 1976 a t Tonbridge Magistrates Court, Kent, Pickfords Tank Haulage of Stroud, Gloucester pleaded guilty to three charges concerning their tank wagon registration mark EMH 423J

The vehicle had been seen during the course of a delivery at a filling station and had been found to be leaking at two of the draw-off taps and also at a union in the pipe connecting a draw-off tap to a compartment

Each leak formed the basis of a separate charge under Regulation 11 of the 1957 Regulations and fines of £30.00 were imposed for each offence with £20 00 costs

Conveyance Matches Carried

At Sevonoaks Magistrates Court on 27th August 1976, Clive Irwin Day the driver of a Total tank wagon, pleaded guilty to a charge of carrying matches on the vehicle whilst conveying petrol

He was fined £60 00 and ordered to pay £10 00 costs

Dangerous working conditions or equipment, inadequate training or inIormation for employees, any many other aspects, are the direct , responsibility of the employer. Neglect ' of these responsibilities, particularly when casualties are the result, can now mean an Improvement or Prohibition Notice, very heavy fines and even imprisonment.

It is not a bit of good to say that the victim of an industrial accident "should have known better" it's the boss's direct legal responsibility to ensure that his employees do know better, and are backed-up by the correct equipment and working conditions.

Conveyance by Road

At Tonbridge Magistrates Court on 1st S e ptember, 1976, Osiers Transp ort Services Limited, of 599, London Road, North Cheam, Sutton, Surrey pleaded guilty to a of failing to k e ep locked the filling open1ng of their tank wagon registration mark JGK 423N

Their driver, Frederick Garnham pleaded guilty to a similar charge and in addition to a charge of carrying matches

The firm was fined £10 00 whilst the driver was fined £10 00 on the first charge and £20 00 on the second

Conveyance Unattended Vehicles

As a result of leaving their petrol tank wagons unattended, two drivers appeared before the Gravesham Magistrates Court, Kent on 23rd June 1976

Both pleaded guilty and were fined £10 00 with £10.00 costs. The circumstances were that both vehicles had been parl{ed on a main road whilst the drivers were in a cafe They were not able to see their vehicles from within the cafe and the distances to the vehicles were 91 f eet and 123 feet respectively.

THE TESTING OF NEW AND EXISTING PETROLEUM SPIRIT STORAGE TANKS

This article, originally given as a talk by Mr. Beer, and published in "The Bulletin" some years ago, is still, we feel, of topical interst to our readership, especially those newly appointed.

I propose to deal mainly with the testing of new tanks and then to pOint out such deviations as to make such requirements and procedures applicable to the testing of existing tanks.

I do not set myself up as an expert who knows all there is to know about the testing of petroleum tanks, but rather as a former practising Local Authority Petroleum Officer who perhaps by nature is of a mechanical and an enquiring frame of mind and who has accordingly given a little more usual thought and research to the matter of tank testing.

Why did I into this matter? Let me ask you what procedure do you adopt in tank testing how do you test storage tanks to ascertain their soundness? _ like most of us I suppose a pressure test _ and what margin do you allow for a drop in pressure, and it is no good to say that is if you do not adopt the procedure I am going to advocate Shortly that you do not make any allowances I used to, but I was not really satisfied with this procedure and that is what caused me to make the change.

After the change it always annoyed me when a fitter, after there has been a small drop in pressure in a tank test with which he has been concerned, to say "Oh, that should be alright, I expect you will allow me a quarter of a pound, they always do in so and so".

I experienced this remark in one partinstance where after correcting for t ' emperature and barometer there had been a drop of one eighth of a'pound. As it was a Saturday I suggested that nothing would be lost if we left the test on over the weekend, and if everything was in order the PreSSure would revert back to the original, knowing of course that as there was a leak-

age, there would be a more noticeable drop over the weekend. The site was at the bottom of a small hill from each direction and over the weekend, due to violent thundersto rms the excavations nearly half filled with water. This found our leak for us and it was in the welding of a seam. It is true that it was only a pin hole and may not happen frequently but I think it is apparent that such small leakages could get through and could create unnecessary hazards.

I have gone to some lengths to make this point because I feel we should approach the matter of tank testing with a little more prec1s10n. I feel we should have more of a laboratory approach rather than allowing some small arbitrary figure of a quarter or half a pound for possible errors.

In other words, we should make the necessary corrections but should make no allowances.

It is really about such corrections and simple apparatus for applying them that I want mainly to talk.

I do not propose to deal in my initial remarks with special tests on special tanks but rather with the everyday gas, be it air or nitrogen, testing of ordinary 500-5,000 gallon underground tanks.

Basically all we have to do is to apply a pressure generally 10 Ib/sq.in which is registered on a pressure gauge, and if there is no drop in the indicated pressure after a period, usually twenty-four hours, the tank is passed as sound

How delightfully easy it was as Simple as that. this is not so

it would be if But I am afraid

You see, as in our schooldays, we are still troubled with Boyles and Dalton or Charles Laws.

I am sure it is not necessary for me to go into these in detail, always provided that I was able, but you will remember that in:

Boyles Law the volume of a given mass of gas at constant temperature is inversely proportionate to its pressure.

In other words, PV = pI VI

In Dalton or Charles Law the volume of a given mass of gas at constant pressure is proportionate to its temperature.

In other words, V _ Vi '1 '11

Now combining both Laws PV PJVI l'

Where

T P initial pressure

V initial volume

T initial temperature

PI= final pressure

V'= final volume

T'= final temperature

(The temperatures and pressures being stated as absolute)

As in the case of a tank we may have under test, the volume is a constant then we have

P pi T '1,orPXTI=TXPI

What, therefore, I suggest we must do is to take both the pressure and temperature of the gas in our tank accurately and in absolute figures and it is here that I may run into some lack of agreement.

But let me get one thing out of the way. I think you will agree that a drop in temperature will cause a drop in pressure, and vice versa, but how much. I will explain the mathematics a little later but would ask you here to accept a figure of .09lbs, or 1/11 lb. for each lOCentrigrade variation and as you will be aware such variation can be directly ascertained by an ordinary mercury thermometer, absolute zero being 27SOC. below zero, usually marked on centigrade thermometers or the melting point of ice

The other point which usually presents some argument is on the question of absolute pressure

Now absolute zero pressure is a perfect vacuum and is in fact the height of the barometer below its level at the time of reading. Unfortunately we have no fixed point as with the thermometer from which to start as the ' ordinary or Bourden tube pressure gauge is simply a comparitor of the pressure in the vessel which is being measured and the pressure of the gas in our case .the atmosphere in which the whole thing is situated.

To state some figures the height of the standard mercury barometer is 30 inches, which represents a pressure of 14.71bs/sq.in.

If, therefore, atmospheric pressure varies between the start and finish of a tank test, our comparitor the gauge will be affected. In other words, we must make a correction for barometric variations. Nothing can convince like a practical demonstration and I have therefore brought along a little bit of homemade apparatus and here I should say "with apologies to Mr. Heath Robinson"

First of all to demostrate a temperature fluctuation.

Here we have a small airtight container connected to a pressure gauge into which we put a pressure and then will vary the temperature.

Now to demonstrate fluctuations of barometric pressure.

Here we have a small container with gauge attached, both of which are in an outer container to which also a gauge can be attached.

A pressure can be put in the inner container (from the outside) representing a tank under test, around which the pressure can be varied in the outer container, representing atmospheric pressure.

If now I pressurise the inner container with a certain mass of gas which as there is no leaking will remain a constant, and without any outside influence other than changing the outside pressure, the inner gauge moves down or up according to whether I increase or decrease the outside pressure; this, I think, clearly demonstrates that barometric variations affect the indicated pressure of a tank under test.

Having, I hope, convinced you that variation of temperature and Qarometer do affect the issue , it now remains for me to show whether the variations which are experienced in p r actice are significant, and I think I will also be able to do this

You will remember at the start I gave a personal experience of one eighth of a pound drop indicating a leakage which was subsequently found, proving, I think, that a variation as small as that is significant.

Now we can revert back to our formula PT I = Pl T and Assume we start with a pressure of 101b./sq.in which rounding off our 14.7 to 15 is 25lb./sq.in.abs

That our initial temperature is 12°C or 285°C. abs. and there is an increase to l7"C or 290°C. abs. "

We have 25 X 290 pJ 285 X p i 25 X 290 285 7250 285 25.44 for 5°C. rise which in round figures is .09 or 1/11 lb for each 1°C. variation, which is quite significant, because it is not at all uncommon to get temperature variations of 5°C. and more.

I do not need to use formula to show significance of barometric variations.

As mentioned previously, the height of the standard mercury barometer is 30 inches and represents a pressure of 14.7 lb/sq.in. Con v erting one to the other and again rounding off 14 7 to 15 lb/sq in. then two inches of mercury = 1 lb/sq . in . In other words a change of barometer of two inches makes a var i ation on the gauge of one pound , one inch of half a pound, half an inch of a quarter of a pound, and proportionately Such v ariat i ons are bound to be significant as in time of meteorological deep depression variations of up to one inch in twenty-four hours a r e not infrequently e x perienced and with a la r ge temperature change as well, I have now a corre cti on of as little as one pound !!!

This I think y ou will agree proves the n ece s sity for makin g such corrections.

Now for the apparatus and procedure to do the job

We will assume we have ar rived at that part of th e pr og r ess of t he installation when the t a n k i s to b e t es t ed

I sugg es t it s h ould b e te s t ed wh e n i n position

I suggest a defini t e dril l so t ha t me mb ers of our own staff and t h e p ump a n d tan k fitters, know what exactly i s n eecie d and c o nfindence is set up on both s ide s .

I suggest also we should provide ourselves with a couple of accurate and reliable gauges of 15 lb./sq.in capacity together with a portable barometer to ascertain pressures. A 15 lb./sq.in gauge seems to be about the most suitable size because it is able to withstand the initial surge when the valve is opened to a tank under 10 lb./sq.in.pressure which a 10 lb/sq.in.gauge is not so able to do. The gauge should have about a 6in. or 9in.diameter dial so that the graduations can be in relatively small increments.

We should have a supply of what I call temperature tubes which may be borrowed by fitters, etc , when preparing tanks for test, together with other sundry apparatus the need for which will become apparent to you as you do your work.

Having received information that a to be tested a temperature tube is made before the fitter applies the pressure. quickly become accustomed to this drill.

tank is available He will

If such pressure is applied to the tank by air pump there will be a heating up. If by air or nitrogen released from a pressure bottle there will be a cooling. I would therefore suggest that three or four hours must elapse between the application of the pressure and the start of the test in order that the temperature may stabilise.

As I feel it is always better to try and reduce the possibility of change of temperature as much as possible, whenever I can I always endeavour to start and finish a test as early in the morning as can be. The reason for this being that night time temperatures are more likely to be similar to each ot4er than those of daytime when the effects of sun and clou,d can create quite large variations. It is also better to cover the tanks wherever pOssible.

Having personally taken the temperature, barometer and tank pressure, of which careful note is made and ascertained by a soap and water test that the control valve is not leaking, the gauge should be removed and the fitting sealed to prevent tampering.

After the lapse of twenty-four hours the readings are again taken, the corrections applied, and if there is no drop the tank passed as sound.

If there has been a drop in the corrected pressure the tank will be leaking and it will be necessary for this to be rectified, usually by the fit t er, and the whole procedure gone through again

On the seco n d visit I like to ascertain and appl y the corrections , working out what the pressure should be show n on the g aug e befo r e turning on the cont r ol v al v e as th i s Seems to be far more effecti v e than t o a f te rwa r d s wo rk out somethi n g that will ju s ti f y a v ariat io n in p r essur e

Having done all this I am of the opinion that NO allowance should be made. The tank is either SOUND or NOT SOUND.

There may be a very slight "blow" f t rom one or wo of the manhole holding down bolts or in th gasket which in themselves would not be. but n _ every ser10us, o can say what th1S represents and until tank 1S proved to be absolutely sound any drop 1n pressure could represent a small blo hI· seam weld. woe 1n a

. I think I have covered the various points I w1shed to make regarding the test· f b 1ng 0 new tanks, ut before passing on, there is one particular thought I would like to leave with you.

:ou will remember my reference to a drop of one e1ghth of a pound representing a small 1 ak Now 1 t' e age. e s assume that we belong to the school of thought that makes no corrections for temperature and barometer.

If there had been variations which made the pressure rise one eighth of a pound or more, that leakage would have been entirely masked and of course quite a large leakage could be masked if variations are large, maybe representing an increase of up to half, three quarters or even one pound and far more than that if we are also prepared allow half or three quarters of a pound as well.

Cases also arise where there should be an increase in pressure of "so much" but where in fact the pressure has remained the same or has increased, but a significantly less amount, in which case there would of course be a leakage.

On the other hand, the testing of tanks takes up valuable time and fitters' wages, so that if the variations cause a drop in pressure then it is only fair that we should acknowledge this also.

Before it was my practice to make the corrections to which I have referred, there were many occasions where there were somewhat unexplained variations about which I was not entirely happy. Since, however, adopting the correction procedure some 24 or 25 years ago, I get a personal satisfaction that I am now passing only really sound tanks and at the same time being fair to the other side. You know it is quite a sobering thought that if we make an allowance instead of applying corrections we may be passing a leaking tank as being sound.

I think it is true to say, if we have said a tank is leaking, then one or more leaks have always been found.

Pipe lines

Although the quantities which could get away through a leaking pipeline would most likely be nothing like as serious as from a leaking tank, there still would be little point in assuring soundness of one without the other.

Owing to the small mass of gas in pipelines as compared with a tank, the same problems do not arise although the question of temperature can give considerable variation if we use the two hour duration test.

As I see it there are two methods, both using a pressure of ten or more pounds per square inch, the one where the pressure must hold for two hours and the other a soap and water test. Personally, I prefer the latter. It is quicker, saves a second visit or hanging about for two hours and certainly picks out the smallest of leaks.

All that is required after the pressure has been applied is to go over all joints, elbows, sockets and connectors using a good paint brush and a supply of water to which detergent has been added, using a looking glass to see underneath or at the back of pipework. Any leakage of course will be shown up by soap bubbles.

I always insist on testing vent lines.

EXisting tanks

As you will perhaps know, it is suggested that these should be tested after 20 25 30 years and thereafter by two yearly 'these periods being specified as 25-30 years is anticipated life of a tank.

Two methods are open to us.

1. A pressure test of from 5-10 Ibs/sq.in using nitrogen or an inert gas (air must NOT be used as it could form an explosive mixture, particularly on release).

The tank must be bottomed and by this I mean that the last few gallons which cannot be removed by the dispensing pump must be taken out through the dip pipe by a semirotary hand pump on top of a length of piping which goes right to the bottom of the tank. The pressure can be applied to tank and pipelines together after the top of the vent pipe and the petrol pump has been blanked off. The same principles as mentioned for testing new tanks should be employed.

If leakage is found then tank and lines would have to be tested separately.

2. An ullage test which is suggested by the Home Office I do not propose to go into the pros and cons of each type of test. The ullage test is carried out on the tank by disconnecting the lines and completely filling the tank, taking the dip at the start of the test and ag a in after twent yfour hours

The ullage is taken and not the dip reading as the former involves far less disturbance of the spi r it level than d oe s the latter

Again this sounds most simple but believe me it is not so simple, as experience may have shown of you.

Now for a few helpful hints on the ullage test.

(a) The spirit to top up should be delivered the day prior to the start of the test in order that the temperature may have time to stabilise. I do, however, suggest a reading should be taken and a rough check made in that first twentyfour hours in case there was a large leakage at the top of the tank which had not previously shown up because a tank is seldom completely filled.

(b) It is surprisingly difficult to take a consistent reading, but I have found a most effective method is to have a small brass rod graduated in 1 / 10 in. with a sand blasted surface and adjustable shoulders to rest on the top of the fill pipe.

(c) The level of the spirit should be below the bottom of the neck of the tank otherwise air or vapour will most likely be at the ends and relatively small

variations of temperature, etc., will cause the most amazing differences in liquid level.

(d) Disconnect lines, particularly the vent lines, otherwise variations will be set up.

(e) Finally, although an ullage test may put on a tank, the lines must be test ed by pressure and as they are undergroun d this must be a duration test.

There are of course other factors, other methods of testing tanks and other types of tanks with which I have not had time to deal. I refer of course to the soap and water and also the hydraulic method of testing tanks, together with the testing of large above ground storage tanks, and whilst I do not intend to deal with them initially, I will be pleased to do so should you ask about these things in question time.

In conclusion I hope I have been of some help and interest, and if it has only made you start to think and if you go back to your own areas to further investigate this subject for yourselves, I shall have been more than amply repaid for any time and effort I have used in preparing this.

BRANCH REPORTS

South-Eastern Branch News

On 4th February 1976 a party of members visited the works of Dresser Europe S oAo at Bracknell. The programme consisted of a talk on the latest pumping and dispensing techniques into which the company are researching and the eq uipment that can be expected on the forecourts and on the industrial scene in the near future. The party then toured the factory to see the 'nuts and bolts' o After a break for lun c he on during which an opportunity was afforded for those present to discuss problems experienced in the field, the party was shown over the company's new testing bu i lding.

The Branch has expressed its thanks to the company through Alan Butcher and his colleagues for a successful instru ct ional day

The Annual General Meeting of t h e Br anch was held at Middlese x House Vauxha ll Bridge Road, London , S oWol at a om on 6th April 1976 It was preceded by a short c ommittee meeting at Which the situation of th e Br anch was diS c ussed but no decisions were t ak e n no r an y recommendations forth c o ming

Mr o H.T E o Jackson took the chair with 17 and 3 Associate Members also present. The minutes of the previous Annual General Meeting Vlere accepted and apologies from 16 members were recorded.

In his remarks Mr. Jackson referred to the three meetings held and stressed their value. still the main need and he effort to be increased

in the past year Recrui tine was urged for the

The secretary reported on the limitations imposed by the financial situation of the Branch and the manner whereby corners were being cut. The support received from the General Secretary in offering to meet any deficit incurred was heartening but the Branch A GoM. had been brought forward to enable those officers and emembers attending the ASSOCiation A G.M to have a clear picture of the state of the Branch . The proposed tie is still the subject of Emergency Committee considerations and Mr. Riddett had attended one meeting of that committee on behalf of the branch.

The secretary stated, with regret, that, owing to personal nressure h e would ha ve to decline nomination in 1977.

The Treasurer submitted a balance sheet showing a cash balance of £13.89 which would need to be reduced by a sum for postage outstanding, The balance sheet was accepted.

All the officers offered themselves for re-election and were returned with no other nominations forthcoming:-

Chairman Secretary Treasurer

H,T,E. Jackson M,E, Smith D, Riddett

G,L,C G,L.C. Hampshire C.C,

Once again the committee would have to be small and, after the secretary had expressed his gratitude for the support received from his outgoing colleagues, D, Taunton B.A,C, Sirey W. Rigby

Surrey C,C, and Berkshire C,C, were re-elected and E. Sussex C,C, was nominated and elected.

Under the heading of any other business a general discussion on the future programme took place and the secretary was charged with preparing a number of visits and meetings for which he received suggestions and offers of assistance. The A,G.M. felt that there is strong ground for increase in capitation fee but none for an increase in subscription, From various speakers the value of the Bulletin was stressed.

A,G,M. closed at 12 •.15 p,m and was followed by a lively discussion on subjects which included G,R,P, petroleum interceptors: an H, & S,E, letter relating to the use of radio transmitters on forcourts during vehiCle charging: the interpretation of regulations pertaining to tank wagon approvals by H. & S,E,; the problems of maintaining fire extinguishing apparatus in car parks and information regarding a policy for sub-standard installations. This latter item brought forth a plea for a nationally agreed policy for which the meeting felt the Association was the ideal medium.

After a late luncheon break the meeting re-assembled for a talk by Mr, H,E McCarthy, Senior Sales Engineer of Emco-Wheaton U.K, Limited and an Associate Member of the Associ.ation,

Mr, McCarthy commenced by demonstrating the developments in open-fill man-lids since their inception. To emphasise the comments he made his company's copy of the film of tank wagon compartment engulfment fires was shown. The film deals with the comparative behaviour of steel, aluminium and g.r,p. carrying compartments in similar fires, At the end of each fire the effect on the openfill lid is high-lighted. Mr. McCarthy completed his talk by exhibiting the advanceS made in the design of draw-off cocks (faucets) and foot-valve mechanisms together wi th , innovations in the construction of internal dip pipes.

Such is the parking situation in London that Mr, McCarthy was unable to bring more than his car boot would hold. In expressing their appreciation the meeting asked if a further apportunity might be forthcoming whereby they could extend the knowledge so far gleaned. In his reply to their thanks Mr, McCarthy promised to try and arrange someLhing further.

South Eastern

On 27th October 1976 a party of stalwarts visited the works of Emco Wheaton U.K. Limited at Margate.

After a welcome and introduction from our hosts which included an opportunity to inspect some later developments in fuelling equipment we embarked on a tour of works. Coupled with the orthodox casting techniques we were able to see the results of innovations that are being adopted. The tour terminated at the company's tanker display unit where many of the components are fitted to a cutaway tanker compartment thus permitting a detailed inspection of their operation in situ.

After an informal luncheon we were shown the I.C.I film' Incident Rendered Safe' made with the co-operation of the Police, Emergency Services and Industry.

The visit could not be complete without a discussion session and we left after a lively and interesting period of question and answer which brought out several points of interest to officers encountering the equipment in the field.

0ur hosts were left in no doubt as to our gratitude for the trouble taken .

HUNDREDS OF OIL TANKERS MAY RISK EXPLOSIONS, SAYS SHOCK REPORT

Hundreds of giant oil tankers using a safety system devised to prevent explosions could be in risk of blowing up like the Berge Istra because valves and seals are not working properly. This disconcerting lesson follows directly from a new theory explaining why the 224,000-ton supership sank, almost 10 months ago, creating one of the strangest and most expensive losses in maritime history.

What gives the theory special impact is that it was advanced at a shipping seminar in London recently by the owners themselves. It comes after a report from the Norwegian classification society, Det norske Veritas, showing how vulnerable these key components are in "inert gas" systems which are now compulsory on all crude oil tankers over 100,000 tons.

BY TONY ROCCA

This . article first appeared in The Sunaay Times, October 10th 1976.

This system, by which explosiye gases emitted from crude oil are neutralised by nitrogen and carbon dioxide flue gases created by machinery either aboard ship or ashore, has previously been considered entirely safe. But a survey by Det norske Veritas has revealed that the impossible, an "inert gas explosion," can theoretically happen.

In 137 inert gas installations it examined at random, nearly three-quarters were found to have faulty blower systems, which propel the gas; more than half had damaged scrubber units, which cool and clean the gas with water; and almost a quarter had something wrong with the seals and valves which control the gas supply.

The Owners of the Berge Istra, Sigval Bergeson of Norway, say it is likely that these seals and valves, each about the size of a dustbin lid, caused the loss of their ship, which was more than a quarter of a mile long yet sank within a minute of being ripped apart by three huge explosions. The company's maritime operations director, Captain Ingolf Stangeland, told the seminar recently: "We have told our officers and crew members very strongly and very precisely that they should not have a false feeling of safety because their ships are inerted."

Two Spanish seamen were the sole survivors from the crew of 32 when the Berge Instra blew up on December 29, southwest of the Philippines, and they have given vital evidence enabling the company to piece together the likely sequence of events in those last few minutes.

Because the ship was a "combination carrier" taking iron ore to Japan after delivering crude oil in Brazil, its empty wing tanks would have been inerted to minimise the risk of explosion. The slop tank still containing oily deposits, would have been in need of a top-up of gas at sea before the ship could safely dock and discharge its new cargo, however.

Scrollber . . -_-I

The blasts tha1:sank a t anker

When the topping up was complete, three safety devices should have made the system secure. A water seal on the 20-inch gas pipe leading from the ship's scrubber house (see diagram) should have filled with water; a non-return valve above port wing tank 10 should have closed automatically; and a butterfly valve in the slop tank itself should have been shut tight.

But, Stangeland says, if the butterfly valve were leaking or not closed, the nonreturn valve stuck in an open position, and the water seal empty entirely plausible after weeks without use then there would have been nothing to stop hydro-carbon gases going b a ck through the pipe and entering the

TECHNICAL CORNER

Presented by PHOENIX

WHAT'S PRESSING?

Most people are familiar with the check valve which is opened b y pressure on its head and which closes when either this pressure is removed or a back pressure develops. We all hav e valves not unlike this in our veins.

There are some valves, however, which are arranged to open only when pressure is exerted on their skirts. Examples of these are to be found in the regulator and by-pass valves of some petrol pumps. The skirt is attached to the bottom of the valve s t em and when the pressure on one side of the skirt exceeds the on its other side, a force is available which, unless restrained, will move the skirt and hence the valve via its stem.

The strength of th e available force depends on two things, namely, the difference in pressure between the t wo sides of the skirt and the area of the skirt exposed to the pressure differential. Let us a ssume that the skirt has an exposed area of two squa r e inches ; then , if th e p re ssu r e differential is 20 p s.i. g ., the mo v ing fo rce is 40 lbs. Mov e ment can be opp o sed b y a sprin g. I f , for e x ample, the sp r in g exer ts a force of 30 Ibs ., then in th e case quoted th e valve will n o t bu dge until the pressu re dif f erential at its s kir t ex ce e ds 15 p.s i.g Use o f t his f a ct is ma d e in t h e l eak detecto r va l ve s t o b e f ound o n the pressu re l i nes of som e rem o te pumping inst a ll at ions.

P re ssu re bui l t u p in a l i ne b y th e re mote pu mp re main s in th e l in e after the pump h as s t opp e d p r ov id e d th at t here is n o l eakage fr o m the l ine and no drop in temperature. So lo n g

scrubber house, itself filled with explosive gas because it contained the heated gas generator.

Result: the first explosion (3 in diagram), quickly followed by the second (4) and third (5) as the fire or hot gases spread

Strangeland told the seminar organised by the magazine Seatrade: " We have no reason to believe that all the built-in safet y equipment should faLl simultaneously " The theory also pre-supposes a failure of the total automatic shutdown and alarm system on the giant ship. But at his home in ' Norway the captain conceded: "It is the most likely e x planation".

' d 1 pressure , and as the line remains under reS1 ua the pressure differential existing at the Sk1rt of the leak detector valve is sufficient the 1 · f h is leakage va ve w111 rema1n open I t ere d pressure or contraction due to temperature rop , is lost, the valve closes and further flow 1S prevented.

Because liquid is v irtuall y incompressible loss of pressure wo uld follo w v er y minor loss Id make th e or contraction of liquid. Th1S wou ·s usuall y system far too sensitive. Th1S snag 1 overcome by arran g ing a bleed hole through which liquid can by-pass the closed leak del · When tector valve to re-pressurize the 1ne. the line is sufficiently the leak detector valve re-opens and all s y stems are "go" once mor e.

The bleed hole is ma de very sm a ll, usuall y sufficient to pass onl y about 3 gallonS per hou r. Th ' the l i ne 1S means th a t if a quart is lost from h ' l d o ff t h e n w 1 e the pressurizing pump is sW1tche it will take at least fiv e minutes to replace the quart when t he pump is switched on. If the h 1" re than o e 1n the 11ne is so big as to pass mo 3 gallons per hour then it will never be possibl e to pressu riz e the line and open the leak detector va l v e until the hol e has been . d f the average repa1re . At th e wo rkin g p re ssure 0 3 remote pump in s t a lla t i o n a t f illin g s ta t10 ns , 11 h o le h av 1 ng g a ons p e r hou r wo ul d p a ss t h r ou g h a a diam et e r o f o nl y 0. 0 13 i n c h

Thus , a h o l e sma l ler th an 0 , 0 13 i nc h in the pr e ssu re lin e wo u ld be revea l e d when d elay in d ischa r ge Occurs at t h e d i s pen ser after the r emote pump h ad b een s witched on. Th e d elay would ge t progressively l onger a s t h e s ize of t he hol e in c reases unt il no de l ivery at all woul d take p l ace when the hole excee d S t h e cr i t ic al d iameter of about 0, 01 3 inch Quite a neat solution to a pressing problem!

HAZARDOUS INCIDENT AT ERDINGTON

The disaster potential that exists in everyday suburban traffic was once more highlighted in an incident involving a petrol tanker at Erdington, West Midlands on Thursday, 23rd September 1976

Erdington is a busy suburb to the North West of Birmingham, lying at the junction of the A38, a principal north-south route, and the A4040, the Birmingham outer ring road.

The first of seven '999' calls to "A tanker overturned and leaking petrol" at the junction of Sixways and High Street, Erdington, was received at West Midlands Fire Service main control at 0900 hours precisely. A first attendance of pump and pump escape from Erdington Fi r e Station and foam tender and recovery vehicle from Birmingham Central was sent on, the first machines arriving at the scene of the incident less t han four minutes later meeting heavy traffic congestion

Sixways, as its name suggests, is a multiple road junction controlled by a large traffic roundabout It was found by the station officer in charge of the first attendance that while neg otiating the island at a point near the mouth of Erdington High Street a large petrol tanker had overturned onto the pavement on its nearside, demolishing a pedestrian guard rail and a post office telephone junction box in the process no persons had been injured the junction bo x had perforated the wall of the t anker and a steady stream of petrol was escaping from t he front tank into the roadway. Petrol was also leaking from the "Emco" valve on top of the fourt h tank and, as the tanker was carrying 5,500 gallo ns of petrol in si x compartments it was p lain that the incident was extremely seriouS.

Pumps were immediately made up to four and 2 foam branches were used to cover the tanker and its immediate surroundings with a blanket of foam. Meanwhile, Police were involved'in the tasks of evacuating shops and houses in the n ei ghbourhood and preventing traffic from further debouching onto the roundabout, Diversions were als o set up at some distance from the accident

BY WEST MIDLANDS FIRE SERVICE

As reinforcing appliances arrived at the incident a further foam making branch and two jets were brought to work, the jets being employed at the edge of the foam blankets to assist in washing the roadway down. It was evident that a quantity of petrol had already entered the drainage system and as it was not possible, or particularly desirable in view of the circumstances, to form a catchment area for the escaping spirit the Water Authority was informed of the situation.

The escape of petrol from the tank valve was controlled when "Epco" equipment was used against the pedestrian railings to ram the valve home, but nothing could be done to lessen the flow from the ruptured compartment.

Erdington is less than two miles from a major Esso Petroleum Terminal, and at an early stage a representative of the firm who had been passing offered the services of the Company in offloading the contents of the damaged tanker, Because of this fortunate intervention it was ossible, using another tanker and hydraulic PumPing gear, to complete this process jn only hours after the initial call, thereby greatly reducing the risk of explosion. When the contents of the Esso tanker had been dipped it was possible to calculate that 1,300 gallons of petroleum spirit had entered the drainage network in the vicinity of the damaged tanker.

The Deputy Divisional Commander, Who had assumed command of operations, now directed that the empty tanker be filled with medium expansion foam prior to righting the vehicle This latter task was to prove more difficult than normal due to the lack of adhesion to a road surface rendered slippery by foam and spirit reSidue, but was finally accomplished using the combined winching power of two Recovery Vehicles. The damaged tanker was then towed away to await inspection by engineers and Customs personnel.

Following the removal of the tanker, crews were reduced to one which was employed in assisting Post Offi ce and Water Authority personnel to wash out underground ducting which, explosioeter

readings showed, were still in a dangerous condition. Explosi@eter readings had been taken consistently throughout the duration of the incident by members of the Fire Prevention Department, and it was a feature of the operation that readings were relatively small in spite of the large quantity of petrol which had leaked. It is considered that this can be attributed to the presence of two major storm drains in the immediate vicinity of the accident which accepted most of the petroleum spirit that flowed into the roadway, the remainder being restricted by the foam blanket which tended to confine vapours to the immediate scene of the incident.

Work in conjunction with explosimeter readings continued throughout the subsequent night and readings were within safe limits with the exception of those taken in two underground ducts. When the readings reached a level well below the explosive range, during the early hours of the 24th September, a decision was taken in consultation with the Police to allow traffic onto the island once more, although the incident was not finally closed until 1640 hours on Monday 30th September.

11 Were received

A number of supplementary ca s h trol appeared during the course of the act10n w en pe in various locations near Erdington. Chief of these was one received hours after the commencement of the incident when a large quantity of petrol was discovered in a brook about a mile away. ot to shoW Explosimeter readings taken here were n safe conditions until 2021 hours.

Petrol is a very familiar commodity, the transport of which is tightly controlled and as safe as can reasonably be made by regulation. Nevertheless, incidents in the past few months point the moral that transport of hazardous substances by road can never be wholly guarant- 'dered that the eed against d1saster. It 1S conS1 West Midlands was extremely fortunate to escape f · in the circumstan the effects 0 a maJor explos10 n ces related above how much worse might the b t ce involved consequences have been has the su s an been one of the many which are currently conveyed along urban highways and which are toxic as well as flammable.

Photograph Courtesy "Birmingham Evening

INDEX

ANNUAL GENERAL MEETING

Birmingham, 29th April 1976 AWARD

B.W.C. Thacker BRANCH REPORTS

Eastern Midlands South Eastern CHAIRMAN'S ADDRESS

Mr. H.T.E. Jackson

EDITORIALS

Making Safe The Future

LEGAL PROCEEDINGS Kent Suffolk

MISCELLANEOUS

An Exercise in Care Boy, 14, Hurt In Petrol Blast Current Legislation

Electrical Apparatus for Explosive Atmospheres Explosion Proofing for Liquid and Gas Containers Hazardous Incident at Erdington

Hundreds of Oil Tankers May Risk Explosion Income Tax Relief on Association Subscriptions

New Film Shows How Britain Deals with Oil Pollution

Parish Council Fights Underground Petrol Tanks 'Poison Peril' Alert in Car Park

Portsmouth Garage Unsafe for Petrol Sale

Pre-Payment Petrol Vending Installation

Price of Petrol The Safety Angle

Reorganisation of the Explosives Inspectorate

Tanker Accident at Audley End

Testing of New and Existing Petroleum Spirit Storage

Vicar Only 'Honest' Customer

What Can We Get

RETIREMENTS

J Beer

TECHNICAL CORNER

What ' s Pressing?

What's The Hold-Up? Who ' s Spitting?

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