They monitor good ventilation – a supply of fresh, clean air coming in from outside or via an internal ventilation system; a reasonable working temperature – usually 16ºC or 13ºC for strenuous work aside from specific laws relating to other conditions; and lighting – suitable for the nature of work being carried out.

The kits contain a T535 CO2 Monitor offering infrared sensors and on-site printouts, a 317-3 CO2 Detection Monitor with headphones and belt/wrist attachments, a pocket-size 540 Lux Meter and a 815 Sound Level Monitor. An advanced version is also available.