Whats this?

[AnthonyB]

One of our H&S guys spotted this and wondered what it was, thinking it was some form of AFD. Its in a car park.

It looks more like an auto fire door magnet, but it's location doesn't seem quite right for that. There is no opposite unit if it was a type of beam (although if no longer in use the other part may have been removed)

[nearlythere]

Vehicle height warning transmitter or receiver?

[Galeon]

beam or flame detector

[FireDave]

It looks similar to movement detectors which are used to turn lights on as part of an energy saving strategy

[Phoenix]

I'd refer to the fire strategy (if there is one).  If not, ask them to tell you (they'll probably have to ask their servicing engineer) - if you're conducting a FRA you really should find out as it appears to be significant.

Or maybe someone on here will know.

[David Rooney]

I've seen similar things in underground car parks... turned out to be some kind of sensor for picking up the build up of dodgy fumes.....

[spanner]

if it is in a car park area I would expect it to be a CO detector or some other form of gas detection.