This sub-class includes the installation of electrical systems in all kinds of buildings and/or civil engineering structures. Units in this sub-class are primarily engaged in: •installation of electrical wiring and/or fittings •installation of telecommunications wiring •installation of computer network and/or cable television wiring, including fibre optic •installation of satellite dishes •installation of lighting systems •installation of fire protection/alarms systems, without later monitoring •installation of security alarm systems, without later monitoring •installation of street lighting and electrical signals •installation of airport runway lighting •installation of connecting of electric appliances and/or household equipment, including baseboard heating