In this Chapter, unless the context otherwise requires,

(39a) "erection, commissioning or installation" means any service provided by a commissioning and installation agency, in relation to,-

(i) erection, commissioning or installation of plant, machinery or equipment; or

(ii) installation of-

(a) electrical and electronic devices, including wirings or fittings therefor; or

(b) plumbing, drain laying or other installations for transport of fluids; or

(c) heating, ventilation or air-conditioning including related pipe work, duct work and sheet metal work; or

(d) thermal insulation, sound insulation, fire proofing or water proofing; or

(e) lift and escalator, fire escape staircases or travelators; or

(f) such other similar services;';