except where the context otherwise requires, include references to the work of individuals participating in the carrying out of such operations; and

do not include references to operations carried out or to be carried out otherwise than in the United Kingdom (or the territorial sea of the United Kingdom).

construction, alteration, repair, extension, demolition or dismantling of buildings or structures (whether permanent or not), including offshore installations;

construction, alteration, repair, extension or demolition of any works forming, or to form, part of the land, including (in particular) walls, roadworks, power-lines, electronic communications apparatus, aircraft runways, docks and harbours, railways, inland waterways, pipe-lines, reservoirs, water-mains, wells, sewers, industrial plant and installations for purposes of land drainage, coast protection or defence;

installation in any building or structure of systems of heating, lighting, air-conditioning, ventilation, power supply, drainage, sanitation, water supply or fire protection;

internal cleaning of buildings and structures, so far as carried out in the course of their construction, alteration, repair, extension or restoration;

painting or decorating the internal or external surfaces of any building or structure;

operations which form an integral part of, or are preparatory to, or are for rendering complete, such operations as are previously described in this subsection, including site clearance, earth-moving, excavation, tunnelling and boring, laying of foundations, erection of scaffolding, site restoration, landscaping and the provision of roadways and other access works.

drilling for, or extraction of, oil or natural gas;

extraction (whether by underground or surface working) of minerals and tunnelling or boring, or construction of underground works, for this purpose;

manufacture of building or engineering components or equipment, materials, plant or machinery, or delivery of any of these things to site;

manufacture of components for systems of heating, lighting, air-conditioning, ventilation, power supply, drainage, sanitation, water supply or fire protection, or delivery of any of these things to site;

the professional work of architects or surveyors, or of consultants in building, engineering, interior or exterior decoration or in the laying-out of landscape;

the making, installation and repair of artistic works, being sculptures, murals and other works which are wholly artistic in nature;

signwriting and erecting, installing and repairing signboards and advertisements;

the installation of seating, blinds and shutters;

the installation of security systems, including burglar alarms, closed circuit television and public address systems.

adding,

varying, or

removing,