Why is it in Hollywood movies every time there is a vent or AC unit someone has fixed little ribbons on it? Is that a thing americans do? Why? The vent in this movie is close to the floor in the toilets of a train. This implies someone got on all fours ON THE FLOOR OF A TRAIN’S BATHROOM to stick those ribbons there for a reason i can’t even begin to comprehend.
You seem to have the imaginative capability of a semi-rotten turnip.
Here’s a hint: maintenance is a thing that happens.
Still lost? Okay, here’s an extremely specific example that actually involved me.
The air system at my job completely failed, so we called in a repair company.
The very first thing they did was go around to every vent tying little ribbons on each one, then fiddled with the thermostat to verify that everything was, in fact, completely borked.
Various stages of the repair process included visually checking for fluttering ribbons, sometimes - gasp! - via the security camera system. And you kniw what they didn’t bother doing after repairs were complete and they packed up and left? Go around and cut off all the ribbons.
Now, go sit in the corner and think about how you’re lowering the average intelligence of an entire planet by existing.
In my first comment I explained how it’s used in COMMERCIAL buildings.
And techs will use tools instead of ribbons, since tying ribbons to ducts, attract dust and can be a fire hazard, most codes explicitly forbid their use.
And great story about the hack company fixing your MUA and leaving their garbage behind since they were too cheap to pay someone to remove stuff they shouldn’t have put in in the first place.
It’s always funny when laymen’s try to say something they saw a hack doing is somehow an industry standard technique or something…. Anemometers are cheap and standard hvac tech equipment. Gives you an exact answer instead of, it flutters….
It’s a Hollywood trope, full stop. People think it’s used in real life since people see the trope and some idiot desk worker wants to think their AC isn’t working.