The following information and instructions apply to permit-required and nonpermit-required confined spaces associated with the KC-10 aircraft. The majority of activities conducted within these spaces are for inspections and routine scheduled maintenance only. Flightline, depot, and other related activities are not referenced in this document. The information presented for each space type is based on the dimensions, inner characteristics, and interviews with shop personnel. Personnel performing aircraft maintenance and support are extensively trained in safe work practices, and work is conducted in accordance with (IAW) strict Technical Order (TO) and Operating Instruction (0I) directives. The TOs and Ols govern procedures such as lockout/tagout and system checks prior to entering the various areas of an aircraft.