The 80 torches you require are going to be very expensive & will need to comply with the appropriate British Standards.
http://en.wikipedia.org/wiki/British_Standards. This is a _really_ bad reference link but it does show the potential can of worms you are being asked to open.
This site looks better www bsigroup com
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All the Australian Standards I have to comply with as an Electrical Contractor start with the AS 3000 Book. The Australian Penal Colony were given the British Standards to start off with & we then adapted them to suit local conditions. Pending on where the team of Engineer's plan to be using these flash lights , you may find they need to comply with numerous other "European Standards" or specific local standards as well.
In order to properly cover your *** , you should ask the Engineering Department to supply you with the appropriate British Standard numbers & any other Standard Numbers they want/need the flash lights to comply with when being used for work.
Explosion/Spark Proof areas as designated as such for 2 main reasons , namely to protect peoples lives & for the Coroner (or some other investigating authority) to find out who to blame when there is an accident of catastrophic proportions in these areas.
I think the "cover your ***" rule & real life examples of what happened if you didn't were mentioned over 100 times in the first year of my Electrical Apprenticeship. Electricians & Electrical Components are on the list of "things" to be heavily scrutinised whenever a large fires or explosion goes off.
If the "Engineers" won't give you the Standard Numbers that they need their "explosion proof" flash lights to comply with , I'd immediately walk away from the task , they are probably looking for a "patsy" or "fall guy" who they can pass the blame onto in the event something Bad(tm) happens.
JB
Link removed as per the banner at the top of the page - Norm