37 Building, installation, maintaining and repairing services related to oil-platforms and oil pipelines; drilling and servicing of oil and gas wells; oil and gas well pumping; mining services; oil sands mining; setting up, supervision and bringing into operation of oil and gas fields, installations for the extraction, transport, storage and processing thereof, process and industrial plants and installations, buildings, machinery and equipment; construction, installation, maintenance and repair of windmills and wind power plants, of offshore wind mills and offshore wind power plants and of wind turbines, mill towers, mill masts and of vanes