Ventilation grille in to escape corridor

[lyledunn]

We have a really difficult situation where a gas boiler of some 70Kw in a social club has been deemed to be non-compliant in terms of air supply. Its location renders getting to an outside air supply, not impossible, but extremely expensive. I could get the required supply via an adjacent escape route. It appears that BS6798 2009; Specification for installation and maintenance of gas-firedboilers of rated input notexceeding 70 kW does not prohibit such a situation. To the contrary, it provides appropriate advice in ensuring fire safety when installing grilles in compartment walls. Perhaps not an ideal situation but if I am attending to the required integrity then why not. The escape corridor provides an alternative route from a function room for up to 200 people. I would appreciate comment from a fire safety expert. Many thanks.

[Midland Retty]

Hi Lyle

Is the boileroom protected by fire detection?

What type of vent grille are we talking here (ie; is it a grid type or horizontal fins) and will it be mounted at high or low level

[nearlythere]

We have a really difficult situation where a gas boiler of some 70Kw in a social club has been deemed to be non-compliant in terms of air supply. Its location renders getting to an outside air supply, not impossible, but extremely expensive. I could get the required supply via an adjacent escape route. It appears that BS6798 2009; Specification for installation and maintenance of gas-firedboilers of rated input notexceeding 70 kW does not prohibit such a situation. To the contrary, it provides appropriate advice in ensuring fire safety when installing grilles in compartment walls. Perhaps not an ideal situation but if I am attending to the required integrity then why not. The escape corridor provides an alternative route from a function room for up to 200 people. I would appreciate comment from a fire safety expert. Many thanks.

How do you mean Lyle "It appears that BS6798 2009; Specification for installation and maintenance of gas-firedboilers of rated input notexceeding 70 kW does not prohibit such a situation." ?

[lyledunn]

Boiler room has a heat detector. grille; not sure as it is something we are thinking about but I suppose enough free area with intumescent material. Nearlythere, I mean that the make-up grille through a compartment wall is not necessarily a problem, whether top or bottom.

[kurnal]

Sometimes you have to do this, rules needed about management of the boiler room and housekeeping, and as its not sleeping accommodation and as there is an alternative escape route it might be ok. You could consider the level of protection needed for the grill, ie intumescent or smoke, and whether the gas supplyshut off  should be linked to the fire alarm system.

[Midland Retty]

Be sure that alternative exits will take the capacity. Also how many people would you expect to use the escape route passing the boileroom. Large numbers of people can't easily just turn around and head for alternatives if a given escape route is blocked. Are there fire wardens at the club to help marshall people during larger functions?

[Fishy]

Sometimes you have to do this, rules needed about management of the boiler room and housekeeping, and as its not sleeping accommodation and as there is an alternative escape route it might be ok. You could consider the level of protection needed for the grill, ie intumescent or smoke, and whether the gas supplyshut off  should be linked to the fire alarm system.

+1.  Intumescent grilles on their own would be pretty useless for protecting a means of escape.  You'd need a fire & smoke resisting damper.  BS EN 13501-3 is the relevant standard, I think.

[AnthonyB]

Also the boiler room would need to have a smoke detector so as to activate the damper in a timely manner.

Whilst heats get routinely chucked in boiler rooms, it's possible with modern boilers to have smoke heads without a massive false alarm risk.

[lyledunn]

Just  for information; BS54402 2009 which advises on ventilation arrangements for gas appliances, forbids terminating grilles in protected areas, whether fitted with fire protection or not.

[wee brian]

whats this grille for? if it is needed for the boiler to operate safely then life gets even more complicated.

you wouldn't want a false alarm to trip the damper and cause a carbon monoxide incident.

[lyledunn]

brian, the damper activated would trip boiler.

[wee brian]

Yup, that was what I was getting at - so you need AFD that trips the damper and the boiler.

Please make sure you tell the building user about it - I dealt with a building where they lost their heating for a couple of weeks before they realised what had happened!

Better still - use a boiler that doesn't need a vent.

[nearlythere]

Better still - use a boiler that doesn't need a vent.

Other than electric is there such a thing?

[Midland Retty]

Electric boilers (water heaters) dont generally need ventilation - All gas boilers need ventilation regardless of whether they are flueless, room sealed or open flue appliances.

[wee brian]

why would you ventilate a room sealed boiler?