Air conditioning installations; gas scrubbing apparatus; air purifying apparatus and machines; ventilation installations and apparatus, namely, ventilating exhaust fans, ventilation hoods for stoves; air-conditioning installations and apparatus; extractor hoods for kitchens; disinfectant apparatus, namely, disinfectant dispensers for toilets; sewage purification facility, namely, sewage purification installations; water purifying apparatus and machines; deodorising apparatus, not for personal use, namely electric air deodorizers; oil-scrubbing apparatus