Electronic Dispensing System

AN ELECTRONIC GASOLINE DISPENSING SYSTEM

By J. Bridger, Esq. Shell Mex & B.P. Ltd.

The most advanced BP self-service station in Europe opened at Stanbourne Motors, Bournemouth in October. The petrol dispensing equipment which is made by the Westinghouse Brake & Signal Co. is entirely electronically controlled and represents a new generation of .forecourt equipment technology.

The emphasis of the equipment is on simplicity and ease of operation from the customer point of view. There are also benefits for the site operator, who is now able to control electronically from one point, prices and blend ratios of all grades of petrol at all dispensing points.

There are six 91- 101 octane blending dispensers at Stanbourne. Customers 'calling at the site simply drive to one of the twelve fuelling positions. They then press a button on an electronic displ'ay panel suspended from the underside of the canopy, take the hose nozzle from the island mounted dispenser unit, and fill up. At most selifservice stations at present, customers can be involved in up to seven lever and knob operations in order to obtain petrol; this system reduces the required actions to only three.

After serving themselves, customers pay at a console unit. where both volume and cash sale are displayed t'O the cashier on a central computer controlled readmIt.

In addition to the customer benefits, the new equipment has two special advantages for the site operator. He will be able to programme the prices of all grades of petrol in

increments of l/lOth of a new penny on aJl pumps simultaneously from a central price control panel at the console.

Blend ratios of each grade of petrol can likewise be set at the same control panel in 1 % increments. Changing a set of blend ratios on a single conventional blender pump can take several hours to achieve, and a simple price change takes 10-15 minutes per pump.

The simplicity of price and blend programming on the Westinghouse electronic control panel makes a complete blend ratio and price change on all pumps possible in about 5 minutes. The electronic control panel may be sealed by Weights and Measures.

The technique of controlling the blend volves and of price computation is novel and entirely electronic in operation.

Photo-electric pulse counters mounted directly on the meter output shafts send a stream of pulses back to the control console. There they are with a pulse "pattern", retained on the console memory which should apply to the particular grade of petrol being dispensed. If there is a deviation between the pulse stream and the "pattern", an electric signal is sent to an electro-pneumatic converter which in turn sends an air signal direct to the blend control valve in the dispenser cabinet. The relative positions of the high/low ports of the blend control valve effectively control the rate of flow of product through the meters. Therefore when a corrective signal is sent to the blend control valve, one port is fractionally opened and the other one closed by an equal amount. This has a direct effect on the flow through the meters and a revised pulse stream is sent to the control console. If the revised stream matches the set "pattern", no further adjustment is required. This system permits very fine control of ratios and high accuracy is obtained.

Price computation for each grade of petrol sold is derived from the same pulse stream. The unit price is compared with, and multiplied by, the stream of volumetric pulses sent from the meter output shafts. The total cash price of the volume dispensed is continuously displayed at the control console and at the customer display module.

As a to efficiency and operational simplicity, a cash register IS mterfaced directly with the control console. Cash sales information, as displayed 'on the customer display modules: can be transmitted directly from the control console mto the cash register, on depression of a "print" button the cashier. The particular sale is then automatically registered and "rung up" on the cash reoister and a receipt is printed. b

BP recognise that this equipment represents a landmark in the history of petrol pump development both in terms of operational flexibility for the site operator, and simplicity in use for the customer.

The dispensing equipment which is featured on the cover of the "Bulletin" this year shows a further example of BP's advanced dispensing ideas. Here the hydraulic cabinets have been removed from the dispenser islands and located remotely, perhaps near to the tank manholes. Alternatively submersible pumps could be used. The customer display modules have been re-shaped into ergonomically designed ca:binets and the hose itself suspended from a point above the display module in order to reduce the weight of hose to be handled by the customer.

This equipment may represent the start of a plateau in development of dispensing equipment. Although we are aJl the time seeking to improve the simplicity and productii'vity of the automobile fuelling operation, there comes a time when the oncost of expensive dispensing techniques is not matched by tangible benefits such as greater potential throughputs or ease of customer operation. However BP believe that the advanced dispensing techniques and equipment described in this article can, in the right ch·cumstances, make a real contribution to retail outlet profitability.

CAR PARKS AND GARAGES

A Paper given by W. C. R. DALE, A.F.I.P.

Petroleum Branch, G.L.C., at York.

Introduction You may 'Wonder why the Association thought it worthwhile including in a course like this a session on garages. Very much the same sort of thought occurred to me when I was first asked to give the talk. I cannot answer for the Association but certainly the authoI1ity for which I work and its main predecessor are and have been very much concerned to maintain control over garages under the Petroleum (Consolidation) Act 1928. Bullding Regulations The need for this control was only partially weakened by the introduction of the Building Regulations. The Regulations at present are concerned basicaIly with the safety and stability Of the structure. There is talk that in the future they may also deal with the ventilation of garages but no doubt there will be considerable argument about the vires of the suggestion. The current control exeroised over garages by the Building Regulations is in any case pretty haphazard. They are all for better or worse lumped into Purpose Group VIII. This is a group which only barely fits the subject with the result that the Department of the Environment has had already to issue a circular to indicate how they will, on individual application in each case, agree waivers of the Regulations in an attempt to try and make them fit. While I accept the concept of management by exception, the idea of management by general exception would seem to make a nonsense of all.

Fire Precaution Act The new Fire Precaution Act could possibly be stretched to enable fire authorities to require the provision of means of escape and fire fighting equipment in public garages but this would require an Order by the Minister. For the present it is usually only the petroleum officer who can require the provision of means of escape and fire fighting eqUipment under the Petroleum Acts. It is similarly only the petroleum officer who can ensure the provision of adequate ventilation and safe electrics and drainage in garages. Hence the need to continue for the present the exercise of control under the Petroleum Acts. TbeLaw has frequently been argued by some people that a licence IS not necessary to cover the keeping of petrol in the fuel tanks of motor vehicles in garages. Such a view has in fact been expressed by some prominent members of the Association. I disagree with them wholeheartedly. Not wishing to bore you with legalistic matters let me state my opinion briefly:(a) Section I (1) of the Petroleum (Consolidation) Act 1928 provides :_ "Subject to the provisions of this Act, petroleum-spirit shall not be kept unless a petroleum-spirit licence is in

force under this Act authorising the keeping thereof and the petroleum-spirit is kept in accordance with such conditions, if any, as may be attached to the licence ...... " (b) By Section I (2) :"The occupier of any premises in which petroleum-spirit is kept in contravention of this section shall be liable on summary conviction to a fine . . . . . ." (c) In Appleyard v. Bangham 1914 I KB 258, it was held that petroleum-spirit in the fuel tanks of motor vehicles was being 'kept' and this is in some measure reinforced by Grandi and Others v. Millburn 1966 2 All ER 816. (d) Under Section 10 of the Act the Secretary of State is empowered to make Regulations as to the keeping and use of petroleum-spirit by persons intending to use it for certain specified purposes. The Secretary of State has made such Regulations, the Petroleum Spirit (Motor

Vehicles etc.) Regulations 1929, and in Nos. 4, 5 (d), 6 (a), 7 (i) and 8 (i) he makes specific reference to petroleum-spirit being kept in the fuel tanks of motor vehicles. (e) In a public garage, the proprietor, i.e. the occupier of the premises, is not the person intending to use the petrol in the fuel tank of any motor vehicle he is garaging. Therefore, he cannot take advantage of any exemption conferred by the 1929 Regulations and a petroleum-spirit licence is required. (f) If a petroleum-spirit licence is not in force it is the occupier, not the person keeping, who is liable to prosecution. Therefore the proprietor of the garage as the occupier must protect himself by obtaining a licence under the Petroleum (Consolidation) Act 1928.

It has been said that if one follows this argument to its logical conclusion it must mean that if your friend parks his car in your garage at home then you as occupier need a petrol licence. I would not argue against this view; the law can invariably be reduced to absurdity in this way if one seeks to do so. As another example also involving the motor car I would point out that everyone of you who has a motor car regularly infringes Section 4 of the Explosives Act 1875 by manufacturing an explosive mixture of petrol vapour and air in the cylinders of the car's engine. It is, however, not customary to prosecute this heinous crime. This is because we have wise administrators and a wise administrator knows when to administer and when not to administer. In a similar way we in London find it difficult to differentiate between an open air car park and rush hour in Piccadilly Circus. Thus we do not press licensing of open air car parks. However, if the proprietor of an open air car park applies for a licence and there are some who do, then we oblige him unless there is a good safety reason for not doing so.

The Greater London Council with the London County County Council before it has licensed garages for more than fifty years. For the first time the practice has been challenged and that by a public body in respect of a multistorey open-sided car park. We have reasoned with the body and the Home Office has acted as arbiter - all to no avail. In the result a declaration by Chancery is being sought to avoid the unwholesome spectacle of two large authorities squabbling in public. A result is expected towards the end of September.* This may settle the question once and for all, although I, personally, have doubts whether the judgement will be wide enough to secure that Utopia.

The risk in garages Having, I hope, established for the present that powers exist under the Petroleum (Consolidation) Act 1928 to control garages, we should next look at the risk involved. Here I must express views which are my own and may not necessarily represent those of the authority for which I work.

If we consider firstly garages in which vehicles are only parked and no repair work on them is carried out then I feel we must concede that the risk, generally speaking, is low. My experience suggests that if a car does not catch fire during the 30 minutes next after parking, then it is generally good for the night; and most of the cars are good. The risk is considerably increased where workshop practices are carried out. It is in garage-workshops that exposure of petrol occurs, where welding is carried on and where petrol is spilled. When one looks at a proposed garage building one must decide whether it is ever likely to be used for garage-workshop practices and hence should be placed in the higher risk category. In reaching a decision one should, of course, always err on the side of safety.

Fires in garage workshops My experience is that the causes of fires in garageworkshops are few in number but that they repeat themselves again and again. Culprit No. 1 must still, suppose, be injudicious welding on vehicles. There was a time. when one could give simple advice to a welder, namely to Isolate the vehicle on which he was working and that if he was operating near the fuel tank of the vehicl: and not place an asbestos blanket between it and hIs then he should remove the tank. Nowadays thIS adVICe IS far from adequate. A number of motor car use plastic fuel lines. What is worse they sometimes these lines from view in body sections. The lder uses his torch on or near the body sectIOn, melts plastiC fuel line and bingo he has a healthy fire on his hands fed often by the whole contents of the fuel In case you imagine that only small cheap cars have plastIC fuel lines, let me add that both Jaguar and Rover cars are so fitted. The G.LC. did write to the Vehicle Safety Division of the Ministry of Transport (now Department of the Environment) about the matter urging that consideration be given to a suitable amendment of the Motor Vehicles (Construction and Use) Regulations. The answer we got was a relatively dusty one. We were told merely that the

'" In the event this date was optimistic. manufacturers had undertaken to warn workshops of the hazard. Presumably the devil looks after the 'Do It Yourself' experts.

Obviously whenevet petrol is spilled in a workshop there is always a risk of fire. One of the very common sources of ignition of spilled petrol has been inspection lamps without outer globes to protect the glass envelope of the electric lamp. We have had a number of cases where cold petrol has dripped onto the hot glass envelope of the lamp causing it to shatter and expose the hot filament of the lamp momentarily before it burns out. The instant has frequently been long enough to ignite the petrol vapour. In London we try, with varying success, to ensure that all inspection lamps are fitted with outer globes. Resistance to this idea arises for two reasons; firstly the globe makes the lamp heavier and more unwieldy and secondly it is alleged that there is a loss of illumination. Fortunately some factory sealed fluorescent hand lamps are now finding their way on to the market. These are certified as safe, even for Division I danger areas, and what is more they are lighter and brighter than the old conventional lamps.

Another common cause of garage-workshop fire is the use of petrol for cleaning purposes. One's only hope of combating this malpractice is by education.

Fire separation of garage/workshops Because fires are likely to occur in garage/workshops we should ensure that there is adequate fire separation between them and the remainder of buildings. Fire-resistance standards are laid down in current building legislation which is fine except that there are three different sets each varying slightly from the other. In England and Wales the 1967 Building Regulations apply, in Scotland there are the Scottish Building Regulations and in Inner London there are the London Building Constructional By-laws. Perhaps one day a comprehensive code of practice for all garage/ workshops will be produced. Certainly a sub-committee of the Home Ofice Standing Advisory Committee on Dangerous Substances is working towards this end but progress is slow. May I therefore suggest as a standard that the only consideration in determining the standard of fire-resistance for garage/workshops should be the 'cube' of the workshop and that a simple formula for above-groUlad workshops would be:Up to 5,000 cu. ft. 5,000 - 75,000 cu. ft. 75,000 - 250,000 cu. ft. Over 250,000 cu. ft. ! hour 1 hour 2 hour 4 hour

A higher standard should be required for underground garage/workshops and this would be 2 hour below 250,000 cu. ft. in extent and 4 hour above. Generally speaking underground garage/workshops shOUld be sprinklered. While on the question of sprinklers I would like to put forward the proposition that the standard of fire resistance need not exceed 2 hour in any case where the garage/ workshop is fj.tted with an efficient automatic sprinkler system.

Ventilation Some people may argue with the idea that an underground garage may be used for workshop purposes. I think it is

reasonable to accept this idea only if the garage is well ventilated. In any type of garage one should aim at getting six changes of air per hour. In an underground garage at least half of this should be provided by a mechanical extract system. There should, however, always be natural ventilation openings which may also serve as smoke extracts. These openings should be well dispersed and in total area should be equal to 2!% of the floor area of the garage. There is always some difficulty in getting adequate ventilation in a garage workshop because people have to work in it. Under the Factories Act, the workshop has to be at a minimum temperature of 60°F. In this day and age anyway, the proprietor would quickly have a strike on his hands if he let the temperature fall too low. In consequence one is more or less forced into accepting windows that can be closed as part of the 'permanent' ventilation openings. This, of course, is another reason why garage workshops tend to be in a higher risk category than the car park type of garage. When petrol vapour may be present the more ventilation that can be arranged the better. Moreover, the more ventilation openings there are the less will be the heat build up within the compartment in the event of a fire.

So far as pure car parks are concerned, it provides an interesting approach to determine whether we can classify garages and hence the standard of fire-resistance they require by consideration of the availability of natural ventilating openings as well as of the type of garage design. Fire Load Densities The Fire Research Station has produced some interesting figures on combustible material of two popular types of saloon car. In every case the petrol tank of the vehicle is taken as being full. An empty 1100 saloon will produce 4,300,000 B.T.U. of combustible material whereas a 1500 saloon produces 5,630,000 B.T.U. Of course in practice cars are never left empty. People always manage to leave a clutter of paper, wood, clothes and other cellulosic material in their cars so we should add 400,000 B.T.U. to cover this. If this is done the revised figures are 4,700,000 B.T.U. for an 1100 saloon and 6,030,000 B.T.U. for the 1500 saloon. 29 per cent of these totals is due to petrol in the tank of the vehicle and 30 per cent is due to the rubber tyres on the four road wheels and the one spare wheel of the vehicle.

The fire load density is defined as the fire load per unit area and therefore in a garage depends on the type of garage building being considered. Closely parked garage Let us firstly consider the case of a garage where cars are parked nose to tail and side to side. This means in effect that the floor space per car is the area actually covered by the car - you cannot park them closer than that! The llOO saloon covers 62 square feet and gives a fire load density of 76,000 B.T.U/ft'. The 1500 saloon covers 79 square feet but .gives us a higher fire load density at 81,000 B.T.U/ft'. If of these cars had a fibre glass body the fire load would be increased by approximately 4,000 B.T.U/

Drive-in garage Most of the garages with which we deal are of course not crammed with cars in this way. Normally the general public drive in and out. Dare I say that with some women drivers, even an overall allocation of 300 square feet per car ds hopelessly inadequate. But· let us stay with the figure of 200 square feet per car suggested by the Fire Research Station. Then the fire load density for the larger 1500 saloon would be 30,000 B.T.U/ft', plus 1,600 B.T.U/ft' if it has a fibre glass body. Lorry parks In the examples given above, it has been assumed that only cars and light vans are parked. And it is true to say that most garages, unless specially designed have far too low a ceiling to accommodate a lorry. It is suggested that the fire load density in a garage specially designed to accommodate loaded lorries might well be as high as 200,000 B.T.U/ft'. Housing garages There is one other type of garage building which we should consider and that loosely might be called the housing estate garage. The history of the development of this garage type is interesting. Originally the garage comprised only a car parking floor or floors on which cars were parked in marked out spaces. These floors made wonderful football pitches for the kids particularly on a wet day. I am told that courting couples found them useful at night too, which is why the lamp bulbs were always being broken. The result was that the garages were abandoned to the kids and lovers and the occupants of the estate parked their cars on the roads where they could keep an eye on them.

To overcome the problem, many authorities decided that they must divide the garage floor into individual lock-Ups. And here the next mistake was made. To avoid interfering with ventilation the partitions and door of each lock-up was made of wire mesh. Then when it was found that people crammed the lock-ups not only with their cars but with household debris, tins of paint, oil, etc., etc. an attemot was made to reduce the fire risk by providing a of one hour's fire-resistance between each group of four lockups. In the result nobody was happy. The kids and lovers felt deprived but they could still get at cars to damage them when the fancy took them. The car owners, when they dared t? trust their cars to the wire mesh cages, took the precautIOn of covering the mesh with P.V.C. sheeting. This destroyed the ventilation, added to the fire risk and upset fire and petroleum licensing authorities.

In the end it has been found that the only possible solution is to provide high security brick enclosures. For this type of development each garage floor should have ventilating openings equivalent to 5% of the floor area. These openings should be concentrated so as to serve the roadways between lock-ups. A 6-inch gap should be left above and below the door of each lock-up and if this does not give sufficient of air then some air bricks should be provided

ID the partitions of the lock-ups. The lock-up partitions should be of solid incombustible construction and should have a one hour standard of fire resistance.

However, to return to our muttons and the consideration of fire load density. It will be found that occupants of these lock-ups will keep not only their cars in them but also a load of combustible rubbish. If you doubt this may I suggest that you have a look at your own garage when you return home. You may then agree that a fire loading density of

about 100,000 B.T.U/ft" is appropriate for each lock-up.

Fire Grading Post-War Building Study No. 20 on the Fire Grading of Buildings is no doubt well known to you all. This suggests that for fire load densities of up to 100,000 B.T.U/tt· a building should have a one hour standard of fire resistance, fOT 100,000-200,000 B.T.U/ft·, two hours and above this up to 400,000 B.T.U/!1't2 four hours. Fire-resistance requirements If we apply the facts and figures we have elicited we can now start to determine the standard of fire-resistance we should seek for garages used only for parking, i.e. when no workshop practices are carried on. For cars parked closely together in a garage we determined that the fire load density was 81,000 B.T.U/ft". Thus in theory a one-hour standard of flre-resistance should be adequate. One has to be careful here in that more recent work has shown that this is reasonable only for a well-ventilated building. Where ventilation is suspect and this might well be the case as the floor area gets larger a two-hour standard might be more appropriate.

For the drive in and drive out type of garage the fire load density is 32,000 B.T.U/ft'. A one-hour standaTd is more than adequate for this type of building. The Fire Research Station has gone even further in suggesting that if the building is above-ground, is well ventilated (i.e. 2!% of the floor area as permanent openings in each of the two longest sides) and meets other detailed criteria, no standard of fireresistance is necessary if the building is constructed of steel members with concrete floors. This suggestion has not been received with enthusiasm in all quarters but nevertheless the evidence adduced in support merits most serious consideration.

If a drive in-drive oO't garage is arranged below ground, one normally double the fi're-resistance requIrement for Similar above-ground buildings. This implies that the standard should be two hours. However, some of you may argue that at 32,000 B.T.U/ft' the fire load density is so low the one-hour scale that one might regard it as !-hour whleh doubled up for underground location brings us back to one-hour. There are arguments for both views o?e always the importance of good ventIlation d rd . stana IS m heat dissipation For lorry . k th . par s e necessary two hours or more For the ho . t '. . usmg ype garage, a mlglbt be struck at one hour for the lock-up partitIOns and two hours for the main structure. Discussion on fire resistance I have spent rather a long time discussl'ng th' d· fi' IS fire loa mg, re gradmg and and fi.re-resistance . of questIOn and I hope tha.t I have not you too much. What I have been trymg to IS that garages nowadays are lar.gely purpose-bUilt . h' fi mme t elr structures d' and that we can quite sim I d t _ Th' p Y e er . IS being so, it is sensible for the Home Office m Issumg Its Code to set out detailed fireresistance standards rather than leave the matter unhappily buried in Purpose Group VIII of the Building Regulations.

Drainage There are really only one or two other points which I would wish to make on the general subject of garages. The first of these relates to drainage. From a fire risk point of view I see no merit in draining the floor of any garage. If the garage is sprinkiered it might be a sensible thing to do to avoid flooding the garage floor. The same is true if the garage floor is exposed to the elements. Whenever the garage floor is drained, however, the drainage should pass via trapped gullies through an approved petroleum interceptor. In insisting on this we may be paying more respect to pollution control than fire prevention; so, to salve our consciences, I suggest we should limit the size of the petroleum interceptor to a single chamber.

Electrical equipment In dealing with electrical equipment in garages I suggest we should limit our interest to fixed equipment, except for wander lamps which, as I said earlier, should always have outer globes. It is customary to regard any pit or hole in the floor of a garage as being a Division I 'danger area'. 11his view I fully support. However, the Division 2 area currently extends above floor level to a height of four feet and I do wonder whether this height might not reasonably be reduced to 18 inches. This is the height, albeit not without some confusion, that the Americans now appear to adopt.

Means of escape Means of escape and access for fiTe fighting will be required and the usual provision for enclosure and discharge of these will apply. However, I think it is fair to say that in no case need staircases be more than 2'6" wide and that staircases not more not more than 200 feet apart will be adequate.

Fire-fighting equipment In London we have had considerable difficulty in trying to overcome vandalism of fire4ighting equipment in garages. A number of schemes have been proposed some of which made fire extinguishers so difficult of access as to desroy almost entirely their usefulness. Our present thought on. the subject is that in a garage-workshop one should contmue to follow the standard pattern of having fire points each comprising a 2-gaUon foam extinguisher, a 2-gallon wat.erexpelling extinguisher and two buckets of sand. We it reasonable to require a foam type extinguisher (or eqUivalent dry powder type) on the basis that frequently the fi.rst substance ignited in garage-workshop fires is petrol. Moreover, the ext'inguishers can be maintained and will be operated by people who should know how to use them.

In garages where no workshop practices are carried out, petrol is rarely involved in car fires - certainly in the stages. Moreover if the garage is widely used by the public with minimal supervision, the hope of having the equipment satisfactorily maintained is as slight as the hope that anyone wHI know how to use it. For these reasons, we encourage in these garages the provision of hose-reels. Currently we are recommending that the hose-reels should have plastic fitments in the hope that these will not have the same appeal to thieves as brass fitments. Where hosereels are provided in this type of garage we waive all other types of fire extin'guishers. Whet'her vandals will leave alone hose-reels with plastic ·fitments only time wiH tell. But even if they rip the hose to shreds, there will still remain a water supply to which the Brigade can attach its own equipment.