Underground Car Parks

CODE OF PRACTICE FOR GROUND FLOOR, MULTI S T O R E Y 8z U N D E R G R O U N D CAR PARKS

PUBLISHED BY THE ASSOCIATION FOR PETR OLEUM AND EXPLOSIVES ADMINISTRATION

The requirements detailed in this manual are given in good faith and in the belief that adherence to the requirements will provide safe installations. However, the Association cannot accept any responsibility of whatever kind for damage or alleged damage rising of otherwise occurring in or about premises or areas to which these requirements have been applied.

2nd Edition

Jan 1995

RECOMMENDED CODE OF PRACTICE FOR ALL CAR PARKS, MULTI STOREY, GROUND FLOOR AND UNDERGROUND

CONTENTS

PAGE NO

(a)

EXPLANATORY NOTES

1

(b)

DEFINITIONS

1

(c>

REQUIREMENTS

2

(b)

FIRE SEPARATION

2

(c)

STRUCTURE

2

(4

LOBBIES

2

(e)

STAIRCASES

3

2

COMPARTMENTATION

3

3

SPRINKLERS

4

4

VENTILATION

4

5

MEANS OF ESCAPE

7

6

ELECTRICAL AND MECHANICAL EQUIPMENT

7

7

EMERGENCY LIGHTING

7

8

ARTIFICIAL LIGHTING

8

9

NOTICES

8

10

FIRE SAFETY SIGNS

8

11

FIREFIGHTING EQUIPMENT

9

12

DRAINAGE

9

13

GAS METERS

10

14

GAS PIPING

10

15

STAND BY DIESEL GENERATORS

10

16

FLOOR FINISHES

11

1

. OCTOBER 1994

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RECOMMENDED CODE OF PRACTICE FOR ALL CAR PARKS BELOW GROUND LEVEL, ENCLOSED TYPE GROUND FLOOR CAR PARKS ANID MULTI-STOREY CAR PARKS Petroleum spirit may be kept for the purpose of motor vehicles etc., in accordance with the Petroleum Spirit (Motor Vehicles etc.), Regulations 1929. If more than 270 litres (60 gallons) of spirit are to be kept then these Regulations cease to apply, the Petroleum (Consolidation) Act 1928 comes into effect and a licence must be obtained before keeping may take place.

A NOTES 1.

The Regulations refer to quantities in imperial units. Throughout this Code metric units of measurement are used.

2.

In assessing whether a car park will comply with the Regulations it may be assumed that every vehicle's fuel tank will contain 25 litres of petrol and that every vehicle unless otherwise indicated on the drawing will occupy 28m2 of floor space.

3.

The expression 'Car Park' used in this Code may include a garage.

4.

Any car park having less than 50% of each of two opposing sides on every floor permanently open shall be deemed an enclosed type car park.

5.

Throughout this Code it has been assumed that observance of all other statutory regulations and requirements, e.g. Building Regulations, will be covered elsewhere, and this Code deals only with matters under the direct control of the Petroleum Licensing Authority.

B DEFINITIONS 1.

A car park should be regarded as any place where motor vehicles are kept. However, for petroleum licensing purposes, no action regarding open air car parking is normally taken but if it appears that there is a definite risk to surrounding property then licensing may be considered.

2.

An underground car park means any car park which has a ,significant part of its floor more than 1.2m below the level of the surrounding ground. Where the car park is built on sloping ground or considerable areas of excavated ground have been left around its perimeter it will be regarded as underground only if ventilation to the open air is difficult to obtain.

3.

Above-ground car park means any car park which is not an underground car park.

4.

Open-sided car park means any car park which:(a)

has natural ventilation openings at each level direct to the open air equivalent to 2%% of the floor area in each of its two longest and opposite sites. 2%% in two walls equals a minimum of 5% and where this cannot be arranged in the two longest and opposite walls, consideration may be given to other

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arrangements of the ventilation openings provided the 5% direct to the open air is achieved and adequate cross-ventilation is ensured; and (b)

has no part of its floor more than 30m from an open side to prevent heat build up within the structure in the event of fire.

NOTE: Approved Document B of the current Building Regulations should also be referred to.

5.

Multi-Storey Car Park means any car park-in which cars stand on more than one floor.

C. REQUIREMENTS The application for a licence must be accompanied by plans and elevation drawings generally to a scale of not less than 1:100, giving sufficient information to identify the site, position of nearby buildings, etc., and all details of the car park. It must include all levels above or below ground, which shall be in accordance with the minimum requirements below or as may be specially specified by the Petroleum Licensing Authority. 1.

FIRE SEPARATION (a)

Structure The fire rating of the car park structure must be in accordance with the Approved Document B of the current Building Regulations and/or the London Building Acts (Amendment) Act 1939, as appropriate.

(b)

Lobbies Where the London Building Acts (Amendment) Act 1939 applies then the lobbies required shall be provided.

In all other cases the following shall apply:Communication from a basement car park with the remainder of the building must be via a ventilated lobby. The lobby shall be constructed to achieve the same fire resisting standard as required by the Building Regulations for the elements of structure. Communication to a level above by lift or staircase would be via a lobby. Communication from a ground floor car park with the remainder of the building shall be to the same fire resisting standard as required by the Building Regulations for the elements of structure. Lobby separation is not required at the same level unless the communication opening from the car park discharges into a designated means of escape route from the remainder of the building.

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(v)

A fire-resisting self-closing door is always required on any

communicating doorway.

NOTES

(c)

1.

Lift doors may be accepted as doors forming the lobby provided they meet the required standard of fire resistance.

2.

Doors should be fire-resisting, self-closing and open in the direction of escape from the car park.

3.

Any fusible link shutters should be fitted on the car park side of the inner door of the lobby.

4.

No car park should communicate with the only staircase in a building.

5.

No car park should communicate with a staircase or lift discharging into a principal circulation route of the upper storeys of the building unless there are alternative means of escape from the upper storeys. One such means of escape should terminate at ground floor level.

6.

Where an underground car par communicates only with the ground storey, the staircase enclosures may be regarded as forming any necessary lobby provided that its partitions have the required standard of the resistance and the enclosure is ventilated as in (7) below.

7.

Where lobby ventilation is required a 0.4m2 unobstructed smoke outlet should be provided as a minimum.

8.

Where natural ventilation cannot be obtained, pressurisation can be accepted provided it complies with BS 5588: Part 4.

Staircases All staircases affording means of escape direct to open air from the car park should be enclosed at each level to the required degree of fire resistance and lobbied where necessary.

(d)

Plant rooms and ancillary rooms Plant rooms and ancillary rooms shall be fitted with fire resisting doors locked shut and shall only be ventilated at high level if required.

2.

COMPARTMENTATION (a)

No compartment within a car part may exceed the maximum permitted size under Approved Document B of the current Building Regulations.

NOTE

Compartmentation is achieved by the provision of suitably rated steel roller shutters giving the same standard of resistance as the structure, held open on fusible links or other approved means. ~

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3.

SPRINKLERS Sprinklers shall be provided in every underground car park and in any car park exceeding 7080m3. This requirement may be waived where the following conditions are met:(a)

the floor area of the car park is less than 500m2 and natural ventilation openings equivalent of 2%% of the floor area are well distributed throughout the car park space; or

(b)

well distributed natural ventilation openings, direct to the open air equivalent to 5% of the car park floor area are provided; or

(c)

the car park is open-side; or

(d)

the car park is single-storey and does not present a fire exposure threat to other buildings; or

(e)

the car park is sub-divided by suitable solid non-combustible partitions into individual lock-ups.

Any sprinkler system shall be designed and installed to comply with the current BS5306: Part 2 1990 and the Loss Prevention Council Rules.

4.

VENTILATION (a)

Underground Car Parks For underground car parks the general standard of ventilation is not less than 2%% of the floor area and a mechanical system capable of three air changes per hour must be provided. Where well dispersed natural ventilating openings equivalent to 5 % of the car park floor area can be provided, favourable consideration will be given to waiving the provision of mechanical ventilation. Similarly, mechanical ventilation will not be required if the floor area of the car park does not exceed 500m2 and natural ventilation openings. well dispersed, equivalent by 21/96 of the floor area are provided. When the car park floor is divided into lock-up garages by partitions, the area of permanent natural ventilation openings to be provided should be not less than 5% of the floor area of the car park. The openings should be so sited that they tend to concentrate on serving the access roadways between the lock-ups.

(b)

Ground Floor Car Parks (i)

Ground floor car parks should be provided with natural ventilation openings. The openings should be well positioned so as to induce cross currents of air. When the car park is of the open plan type, i.e. without I

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partitioning of car space, the openings should be permanent and not less than 21/96 of the floor area... Open sided car parks are defiied in Approved Document B of the current Building Regulations. The standard of ventilation required is 5% with at least half of this figure on opposite sides.

(ii)

NOTE§ 1. If a natural ventilation opening to a car park is within 2m to openings in other property thus providing a high risk of spread of fire, measures should be taken to minimise that risk. Sprinklers, drenchers, projecting balconies and fire-deflecting louvres constructed of a fire-resisting material (e.g. steel, Georgian wired glass fixed in fire-resisting framework etc.) are examples of protection which will be acceptable in particular cases. Due consideration should be given to preventing smoke ingress into any residential premises. 2. In calculations only the permanently open area of doors, grilles or shutters in ramp openings may be used.

When the above requirements cannot be achieved a mechanical system must be provided for basement car parks as follows:(c)

System for petrol vapour only: (i)

(d)

.

six air changes per hour arranged in two parts, each part being capable of three air changes. A back up power supply is required.

(ii)

metal ducting is to be well distributed to give cross flow ventilation. Ductwork extract points are to give one third high and two thirds low level extraction, and

(iii)

2?4% natural smoke outlets well distributed must be provided; These may be in the form of permanent lights or openable panels.

Combined system for petrol vapour and smoke extraction: (i)

six air changes per hour must be provided for normal petrol vapour extraction

(ii)

in a fire situation the system must operate at ten air changes per hour

(iii)

the fans must be rated to run at 300"c for a minimum of 60 minutes

(iv)

a back up electrical supply to give three hours duration is required

(v)

ventilation openings must be arranged to provide 50% at high and 50% at low level, and

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ductwork and fixings must be constructed of materials having a melting point not less than 800"c galvanised steel ductwork normally meets this requirement Where the danger from toxic fumes is very great an increase in the rate of extraction near ramps and approach ways where bad conditions are likely to occur will be required. Where car parks are on different levels, each should be vented separately so that fumes are not drawn from one car park to another, Ventilation trunking which passes from the car park through other parts of the building should be enclosed in a duct, or fire rated, which maintains the standard of separation for the car park. In certain circumstances, where. non fire rated ductwork passes though a compartmentation wall, a fire damper will be required to be fitted in the ductwork. This will not be permitted where a combined smoke and petrol vapour system is proposed. When it is necessary to require mechanical ventilation arranged in two parts the secondary source of electrical supply can be met by the provision of a diesel generator plant or by batteries maintained on charge and of a capacity adequate for running the ventilation plant for three hours. The following rules will serve as a general guide:-

Car parks over 1000m2 in the area - standby plant required. Car parks between 500m2 and 1000m2in area with less than 1%% natural ventilation openings standby plant required

-

Other car parks between 500m2 and 1000m2 in area - separate circuits from the main are accepted with no standby plant.

Car parks less than 500m2 in area - two systems of mechanical ventilation may not be required but if little or no natural ventilation is provided it will be necessary to provide mechanical input of air. (e)

Smoke extracts Openable windows or other means aggregating to not less than 2.5% of the floor area, arranged to induce cross ventilation or smoke outlets should be provided as follows:(9

situated at high level in well distributed positions along street frontages or adjacent to external walls easily accessible to the fire brigade .

(ii)

be as numerous and as large as possible

(iii)

aggregate not less than 2.5% of the floor area they serve

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6

(iv)

if covered, have breakable covers

(VI

if permanently open, be sited away from exits

(vi)

marked to indicate the area served

NOTE: Generally plant will need to be arranged in two equal parts each capable of providing not less than 50% of the maximum required extract when run separately. Jn the case of 4(c), three air changes per hour and 4(d), five air changes per hour minimum will be required. 5.

MEANS OF ESCAPE (a)

Means of escape should comply with the following guidance where applicable:(i)

BS 5588: Part 3: Fire precautions in the design and construction of buildings: Code of practice for office buildings; or

(ii)

the Current Building Regulations, Approved Document B; or

(iii)

The London Building Acts (Amendment) Act 1939.

NOTE: Generally the requirements for means of escape can be summarised in that no part of the car park must be more than 30m from a fire exit, and the indirect travel distance must not exceed 45m.

6.

7.

ELECTRICAL AND MECHANICAL EQUIPMENT (a)

Electrical equipment, including electric lamps, installed below the general car park floor level must be of a type suitable for use in a Zone 1 hazardous area (see BS 5345).

(b)

Electrical equipment, including car park barriers and ticket machines, installed at car park floor level or within I.2m above floor level, must be of a type suitable for use in a Zone 2 hazardous area.

(c)

All electrical equipment must be suitably protected from mechanical damage.

(d)

Electrical equipment installed within the air stream of the extract ventilating system must be of a type suitable for a Zone 1 hazardous area.

EMERGENCY LIGHTING (a)

BS 5266: Part 1: 1988 specifies the technical requirements for emergency lighting.

(b)

As a general guide, however, artificial lighting should be provided of a sufficient standard to enable persons to move about within any building, to leave any part of a building and to reach a final exit. 2025 1151

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8.

(c)

In internal staircases serving a car park at a lower level than first basement or serving a car park comprising more than one basement storey, emergency lighting should be provided. An emergency lighting system should be from a source entirely independent of the artificial lighting in the car park and staircases, should by itself afford a level of illumination sufficient to enable persons to leave all parts of the car park and should be arranged to come into operation automatically within 15 seconds of the failure of the normal supply. The electrical supply for lighting system may be from a generator or from a battery system.

(d)

Emergency lighting systems are required for basement car parks lower than first level or multi level basement car parks together with any integral staircases.

ARTIFICIAL LIGHTING Electrical lighting, to an average standard of 20 lux and a minimum of 5 lux shall be provided to illuminate the car park and escape staircases. The circuit shall be so designed that staircases and exits shall be illuminated whenever the car park lighting is switched on.

NOTE Further guidance may be provided under Health & Safety Guidance Note HS(G) 38.

9.

NOTICES Adequate notices shall be conspicuously displayed bearing the legend:-

"No smoking No filling or emptying of vehicle tanks" Such notices shall be clearly visible from any part of the car park, the lettering should be of reasonable size but not less than 25mm in height to confirm to BS5378: Part I: 1980 and to the relevant parts of BS5499. 10.

FIRE SAFETY SIGNS (a)

(b)

In an underground car park, exits should be provided with illuminated 'EXIT' notices clearly visible from all parts of the car park. If the notices are of the electrically powered type, they should comply with BS2560: 1978 and one of the power sources should be linked to an emergency lighting system. If the 'EXIT' sign is of the self-luminous type, it should conform to BS 5499: Part 2: 1986. The specification for other fire safety signs, notices and graphic symbols is set out in BS5499: Part 1: 1984.

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8

I

.

11.

FIREFIGHTING EQUIPMENT (a)

Generally it is accepted that where access for fire brigade appliances is acceptable, no hand held fire extinguishers are required but adequate number of notices stating:-

"In the Event of Fire Do not return to your vehicle Proceed to the nearest exit Call the Fire Brigade" must be displayed. The notices should be clearly visible from any point of the car park, the lettering should be of reasonable size but not less than 25mm in height to conform. to BS 5378: part 1: 1980. (b)

When any hand held for appliances are required, then the local licensing authority shall be consulted as to the number and type required.

(c)

Where any car parking floor is proposed at a height of 18m or more above ground level or more than one floor below ground, the Chief Fire Officer should be consulted about the desirability of providing dry rising or failing mains to protect the car park floors.

NOTE: The Fire Authority and Licensing Authority for the area should be contacted in relation to special provision for first-aidfire fighting equipment. 12.

DRAINAGE A surface drainage system should be provided in every underground car park exceeding 500m2 in area. An extensive system is not required and provided that a car park gully is available within 30m of any part of the car park, the arrangements may normally be regarded as satisfactory. In above-ground car parks a surface drainage system is not normally required. Every car park surface drainage system should be passed through a petroleum interceptor. Where the ares is used solely as a car park, a single chamber petroleum interceptor will normally be adequate. Where a car park is used for a purpose additional to car parking, a two-chamber interceptor may be necessary. By-pass interceptors are acceptable.

In no case must the drainage of a car park pass -through the interceptor of an associated petrol filling station. All gullies connected to a petroleum interceptor should be trapped garage gullies with external rodding eyes and back inlet gullies are not permitted. Drainage pipework should be laid to a fall of atminimum of !:40. Floor slabs should be laid to falls of a minimum of 1:lOO towards the drainage gullies. 20251151

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13.

(g)

Petroleum interceptors should be sited within the curtilage of the property, so that access may always be available for cleaning purposes. Care should be taken to ensure that arrangements are made for cleaning: access shall be provided for a mechanical cleansing vehicle to approach and stand reasonably near the interceptor.

(h)

The interceptor ventilating pipe(s) should be as short as practical and terminate not less than 2.5m above paving level. The pipe should not be less than Im above the head of an openable window or other opening into a building nor within a horizontal distance of 3m therefrom.

(i)

Where the invert level of the petrol interceptor is lower than that of the connection into the local authority’s sewer, it may be necessary to provide a pumping chamber. Provided that the pumping chamber is separate and down stream from the interceptor and is fitted with a screwed down double cover. non-certified electrics may be used within the pumping chamber.

(j)

By-pass interceptors may be installed in car parks.

GAS METERS Gas meters may be permitted in both underground and above ground car parks provided that they are sited in a separate room which is ventilated at high and low level directly to the open air. The standard of fire resistance of the separation, including the door, should be to the same standard as that of the building. The gas meter room should not be ventilated directly to a car park. . Where the Gas Supply company determines that ventilation in the car park is adequate a separate room may not be necessary as gas meter units are fire resisting. However. siting should be away from heating sources and electrical switchgear.

14.

15.

GAS PIPING (a)

Gas piping of steel, cast iron or copper may pass through an above-ground or underground car park. Any risk of mechanical damage to the gas piping should be countered by adequate protection.

(b)

Pipework (e.g. soil, gas and water pipes) may pass through a slab or partition required to be fire-resisting. Cast iron, steel or copper (but not lead, zinc or plastic) pipes may be accepted provided that they are not more than 150mm in diameter, fit tightly into the slab or partition and are situated or protected so as to preclude the possibility of mechanical damage. The arrangements should comply with the current Building Regulations approved Document B.

STAND-BY DIESEL GENERATORS (a)

The installation of a diesel powered stand-by generator in an underground car park is acceptable.

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(b)

16.

If the diesel storage tank exceeds 250 litres, then separate storage will be required. However if the diesel stdrage does not exceed 250 litres it will be sufficient to observe the following requirements:-

(i)

The stand-by generator should be in a separate enclosure having a standard of fire resistance of 60 minutes.

(ii)

The enclosure should be effectively ventilated and the exhaust fumes should be ducted to the open air.

(iii)

The enclosure may be regarded as a maintenance plant area and need not be provided with an alternative means of escape. The door to the enclosure should be normally kept locked shut except for access.

(ix)

The door should be of the same standard of fire resistance as the walls, and the doorway provided with a 150mm sill to retain oil and foam in the event of fire.

(v)

If sprinklered, a gully should be provided within the enclosure.

(vi)

The electrical arrangements should comply with the standards specified in Section 6 of this document.

FLOOR FIMSMES (a)

All floors should be of concrete.

(b)

Other materials my be applied to a concrete floor slab. If asphalt, then the specification detailed in the appropriate sections of the Mastic Asphalt Council and Employers Federation Paving Handbook shall be followed.

(c)

Other floor finishing materials will be considered provided they achieve a minimum EXT. FAA rating when tested in accordance with BS 476 Part 3: 1958 and are laid in accordance with the manufacturer’s specifications.

NOTES: 1.

For car parks with less than 270 litres, no licence is required if compliance with the Petroleum Spirit (Motor Vehicles etc.) Regulations 1929 can be secured. Where the Regulations cannot be complied with, licensing will be necessary.

2.

In cases of doubt, the local Licensing Authority may be consulted on clarification of requirements of the Regulations.

The requirements detailed in this manual are given in good faith and in the belief that adherence to the requirements will provide safe installations. However, the Association cannot accept any responsibility of whatever kind for damage or alleged damage arising of otherwise occurring in or about premises or areas to which these requirements have been applied.

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THE ASSOCIATION FOR PETROLEUM EXPLOSIVES ADMINISTRATION A company limited by guarantee in England No. 2261660 Reg Office STOUGHTON HOUSE, HARBOROUGH ROAD, OADBY, LEICESTER LE2 4LP

OFFICIALS HON SECRETARY D.W. Bucknall Humberside Trading Standards King Edward Street Grimsby DN313LU Tel: 01472 341344

HON EDITOR J.A.J. Thompson 44, The Knowle Hoddesdon Herts EN1 1 8LD Tel: 01992 460812 or 0171 587 4577