Protective suits range from fully encapsulating (and extremely limiting in mobility) to form-fitting and meant for specific, mobile activities. They are typically grouped by level of protection (A-D) and come in two primary classes: Carbon/Membrane Suits and Level A-D. Level A-D suits are defined by OSHA, and Carbon/Membrane suits are intended for military and SWAT-style use (when unimpeded mobility is required). CBRNE Tech Index does not include the more common white TyVek-style suits, as they are generally considered a level D coverall and not meant for extended field use.