I was recently at a factory where all production is carried out in explosion-hazardous class ZL 2 halls. I am attaching a few photos with my observations.
The installation has properly made inspection holes for introducing a robot to clean channels. Due to the nature of production, the air in the hall must be at the level of the background that surrounds the plant.
The next observation is a properly performed measurement of air temperature and flow in the channel. Four probes are placed on the diagonals of the channels and connected in a Graetz bridge. Thanks to this, the measurement is averaged. The same was done with the measurement of air temperature in the hall, but here it was not possible to take a photo of the sensor layout.
The last observation concerns the installation of displacement air vents on the duct above the zone of human occupation. As a rule, they stand on the floor and pretend to be columns. There was no room for that here. Additionally, they have a rather oddly placed measurement of the supply air temperature.
