Could anyone please give me some advice on whether a fire door to a battery room can have a glass panel in it or point me towards some appropriate regulations? Someone at my work wants to fit doors with glass panels to the battery rooms as they are always locked to keep out unauthorised personnel. He wants to check the room without drawing the key. My own thoughts are that if there is an exposion (hydrogen from battery charging) a solid door would be much safer. However, I can't find any regulations that specify whether a glass panel in the fire door is acceptable or not. Personally I want to say don't change the present doors but I'd like to back it up with some evidence. I'd be grateful for any help.

Teen
Take the good advice from messy, we have a number of fire doors with vison panels (fire resistant) obviously.

I assume we are talking lead-acid (wet type batteries here). There is an explosion risk from such batteries if H2 is allowed to build up (LEL 4% - UEL75% for H2)

You should keep the hydogen at no more than 1%.

However having said that, modern valve regulated batteries only release very small amounts of H2

If you speak to the battery vendors, they should be able to tell you the H2 discharge rate - then depending on the number of cells in the batteries you can calculate roughly how long it will take to produce a theoretical H2 explosive atmosphere. You will also need to calculate the volume of the battery room.

You may well find if the battery room is big enough, that it could take quite a few hundred hours to get anything close to a flammable atmosphere. This would assume no ventilation at all.

In practice most battery rooms have some ventilation, through gaps around doors etc.

You should have low and high level ventilation in the walls of the battery room, ideally on opposite sides of the room.

If all else fails BS6133 contains a forumla for estimating the quantity of hydrogen produced.

You can then uses BS60079-10 Explosive atmospheres to calculate how much ventilation you require to keep the H2 to less than 1%. Hence the size of the ventilation louvres to give the required air changes through the room

There is also an HSE leaflet about battery rooms.

It would still be wise to have a fire door on the battery room - although in my view this is open to debate depending upon the location of the battery room. Is it a stand along building? If part of a larger building, what goes on in the rest of the building? Occupancy of the rest of the building etc?

If you can't achieve adequate natural ventilation, then forced ventilation should be installed, with a warning alarm if the fan stops working.

If you do the above, whatever type of door you install, it doesn't need to be blast rated.

On the risk control ladder, fitting blast doors is well down the list. You should not be having an explosive atmosphere in the first place to require a blast door!!!

There is an H2 explosion risk, but probably not as much as you might think.

Its easy to develop an Excel spreadsheet to do the calculations. I have got one

In areas where a staff search procedure is invoked when a fire detection system operates, it's not a bad idea to have a vision panel in a room such as this, so that the staff doing the search can see into the room without entering.

However, I would not advocate installing a VP unless the door needs to be a replaced as the expense v risk would be disproportionate.

Thanks for all the advice. I will look for fire and blast doors with vision panels but may ask the person to justify the expense of changing them. It annoys me that the proposal isn't to change them on safety grounds but to save him a few minutes drawing the key out.

The battery rooms have been checked against DSEAR but I will take JJPs info and check them again as it's been several years since our DSEAR assessment was carried out.

Thanks again.

A somewhat fair comment, however there are some key differences between the scenarios

Battery hydrogen is not evolved all of the time.

The Glasgow ICL factory effectively had an unlimited inventory of gas escaping into the cellar/basement etc.

Although the factory should have known, they had forgotten about the lpg pipes, took no precautions (like fix the pipes/re-route them etc)

When charging batteries, liberation of hydrogen is a well know hazard.

As per my last post, explosion rated doors are not necessary if you have provided adequate ventilation for the battery room