This involves structural firefighting and wildland firefighting. Some 40 helicopters were equipped for firefighting operations. The LA County Fire Department has 10 helicopters available for aerial firefighting. The division has six helicopters available for both aerial firefighting and air medical services. The standard fire engine is an apparatus designed primarily for firefighting operations. The Hertfordshire Fire Museum is dedicated to the history of firefighting in the county. They were eventually destroyed during firefighting training. Engineering staff are required to have training in firefighting and first aid. Initially the men worked on road building, forestry and firefighting projects. These fires were already creating a strain on firefighting resources. The U.S. Forest Service also wanted 7 C-27Js for aerial firefighting. It has been used in aerial firefighting. Specialized models have also been produced for aerial firefighting and zero-G training. A Nomex hood is a common piece of racing and firefighting equipment. This is a glossary of firefighting equipment.