Drilling for, or extraction of, oil or natural gas.
Extraction (whether by underground or surface working) of minerals ; tunnelling or boring, or construction of underground works, for this purpose.
Manufacture of building or engineering components or equipment, materials, plant or machinery ; 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 ; 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.