Code of practice for fire precautions in the design and construction of passenger carrying trains

BS 6853:1999 pdf free.Code of practice for fire precautions in the design and construction of passenger carry1ng trains.
6.1 Avoidance of biding places for fire sources
Open recesses and gutter shaped open elements (e.g. for indirect )ightrng) should not be used In passenger compartments. Overhead luggage racks should be designed such that objects placed there are visble from below. Designated staff-only areas should be capable of being securely locked.
6.2 MinimIzing combustible material, and provision for cleaning
The inside and outside of the vehicle should be designed to minimize the accumulation of combustible products. Heater enclosures should be designed and positioned to inhibit ingres. or retention of combustible material. Ventilation systems should be capable of being easily cleaned. Filling point.. for combustible liquids should be designed such th*t spiflages of liquid can be readily seen and cleaned up.
5.3 Litter bins
Litter bins should have a solid construction and should be fitted with a self-closing device, in order to prevent spillage of litter and enable the bin to contain a fire. Their material of construction should be fire resistant in accordance with 7.7.
5.4 Provision for smoking
Where smoking is permitted, an adequate number of ashtray. should be provided. The ashtrays should have a solid construction and should be fitted with a self-closing device, in order to prevent spillage of ash or litter and enable the ashtray to contain a fire. Their material of construction should be fire resistant in accordance with 7.7.
5$ Protection of combustible materials from beaters
The design of heaters (excluding cooking equipment) should be such that the temperature of the surface casing of the heaters does not exceed 60 C in normal operation. Inlet and outlet grilles should be so designed that they cannot be easily blocked.
6.6 Designated luggage areas
Designated luggage areas, where luggage is not within the view of passengers or staff, should be contained in a manner that ensures that combustion of the luggage cannot readily breach the containment, and also that an external fire cannot involve the luggage by readily breaching the containment.
5.7 Catering and cooking areas
Cooking equipment which utilizes oils or fats for frying or similar processes should be designed so that vehicle movements cannot cause a fire hazard from the mobile flammable liquid. Provision should be made for the storage of any such oils and fats such that they are protected from source, of ignition. Cooking equipment which utilizes liquefied petroleum gases (T..PG) should not be used.
5.8 Electrical protection
Creepage and clearance distances should be set with due regard for the propensity of the materials to track and with due regard for the voltage used and whether it is ac. or d.c.. so as to minimize the occurrence of electrical faults. Suitable electrical protection should be provided to ensure that the energy release rate on oirrene of a fault and th. duration of the fault is minimized. This guidance applies to electrical power both as an ignition source and as a power output hazard when in the forn of a power arc.
5.9 Protection against power arcs
Suitable are resisting barriers should be used to proteet the passenger compartments with partieular consideration being given to areas where faults are electrically unprotected other than by substation cireuit breakers.
5.10 Protection against high current circuit breaker output
Suitable shields should be provided to prevent any efnuent from the train-borne circuit breaker acting as an ignition source for materials or debris and also to prevent the degradation of other Bystems 8uch as cables which would increase the risk of ignition should they fail.
5.11 Protection against sparks from current collectors
Suitable shields should be provided to prevent incandescent particles from current collectors from acting
as an igmtion source for underbody materials and debris.
5.12 Cables and wiring
The design and Installation of electrical cables and wiring should be such as to ensure minimization of the rislc of fir, due to internal heating of th. cables or wiring or due to external expure to sources of beat. When d.t.rminrng the siz, of cables, the following should be taken Into account:
a) th. grouping of wires, whether in conduits, bunking or fre, air;
b) ambient temperature, with particular reference to elevated local temperatur, during vehicle operation;
c) the normal and peak temperature rating of the cable;
d) the normal and peak power carried by the cable;
e) the magmtude and duration of the power which might be carried by the cable under fault conditions;
1) the proximity of othercombustible materials.
5.13 Internal combustIon engines: diesel
A valve should be fitted in the supply line such that when the valve is operated the engine shut.s down and the supply at fuel ceases. The fuel reservoir should be contained within a suitably fire resisting envelop. including all pipework at least up to and including the valve. It should be possible to operate the shut down procedure and valve from within the driver’s cab and also from a point external to the vehicle. The means by which the valve is operated remotely should hav, adequate resistance to fire so that it is not disabled by fire before it can be utilized.
5.14 Internal combustion engines: petrol
Where petrol engines are carried on railway vehicles during passenger servxe a risk assessment should be earned out.
6 Materials
6.1 General
Materials are classified into one of a lisiited number of types determined by their position on the vehicle and the type assigned determines the teat regime that ii apphed (i.e Table I to Table 14). There is a distinction made in the tables between interior and exterior performance.
Surfaces are subdivided according to their orientation on the vehicle. The orientation of a surface is critical in determining the risk of flame spread and fire development as it determines the efficiency with which heat can be inputted into the surface. Surfaees are therefor. classified, in decreasing order of fire risk, as follows:
a) “ceiling-ike” (horizontal prone, HP, see 3.1.12.1);
b) “wall-like” (vertical, V, see 3.1.12.3);
c)“floor-like” (horizontal Bupine, HS, see 3.1.12.2).
HP surfaces and V surfaces can be further classifed as limited extent (L) surfaces if they fulfl certain criteria (see 3.1.12.4).BS 6853 pdf free download.Code of practice for fire precautions in the design and construction of passenger carrying trains