We have rather a lot of them in our labs since they were rebuilt, and we need to cover them with an appropriate red cap when we do anything that might trigger the alarms, which happens all too often. We have three or four caps, but there are two sites with ten labs plus prep rooms and store rooms, and a corridor outside four of the labs with seven of these detectors - the ceiling is split into several areas by beams crossing the corridor, and they have a sensor in each area. We could really use a lot more. The caps look like this:
Unfortunately I have no idea who made these - the number shown is its number on the alarm network, not a model number or anything, and I can't see a maker's name anywhere.
Anyone got any thoughts?
Later - manufacturer tentatively identified, I've contacted them re spares and hope they'll reply sooner or later. Thanks, everyone.