Slightly off topic, related laser systems are often used as smoke detectors.
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On our site, one sprawling production building's vast roof space held huge aircon systems etc etc. Also, much data and power cabling, so contractors and sub-contractors often accessed it.
One day, the secondary, laser alarm sounded. Its beam ran about a metre below the long roof's apex, was a back-up to the many individual 'smoke heads'.
As you'd expect, the site fire team responded at 'best speed' while the building's many occupants evacuated and a 'Three Engine' call went out.
The site fire team arrived on scene to find a group of sub-contractors having a picnic lunch, smoking and playing cards.
They'd bypassed the nearby smoke detector heads, but the infrared apex laser was a completely independent system, to be sure, to be sure...
Tampering with safety systems ? Food / Food consumption outside designated safe areas ? Smoking on site ? Gambling ??
They'd ALL sat through the videos, passed the quiz and signed for our site's strict safety, hygiene & security briefing...
Totally Epic Fail.
Aided by the fire team, site security marched those ijit sub-contractors to site perimeter, dumped them on the verge outside the gate.
Their company was barred, and their contractor nearly went broke as word of the incident went around...