Repair and maintenance of acoustic and thermal insulation, fire protection insulation, building insulation, and sound absorbers; construction of fire protection insulation, thermal insulation, and sound insulation, namely, installations of building, vessel, aircraft, train, and industrial insulation in the nature of fire protection insulation, thermal insulation, and sound insulation; installation of fire protection insulation, thermal insulation, and sound insulation

fireproof doors and windows made of metal

Sound absorbers for smoke installations, exhaust gas installations, air supply installations and steam blow-off installations or cooling units