I happen to have a memo to the Manager, Technical Programs Branch, AGL-230, from Aircraft Maintenance Division, AFS-300 requesting clarification on “Servicing of Aircraft Oxygen System” dated December 23, 2008 as follows:
Title 14 Code of Federal Regulations (14 CFR) does not define the term servicing when used in the context of aviation maintenance. The terms used by 14 CFR are maintenance and preventive maintenance. Based on the type of “service” to be completed, the job activity is classified as maintenance or preventive maintenance when using the definitions found in 14 CFR part 1.
· Preventive maintenance means simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations.
· Maintenance means inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventive maintenance
Therefore, the “servicing of aircraft oxygen system is considered maintenance not preventive maintenance. Operators certificated under part 91 shall use mechanics or maintenances entities authorized under 14 CFR sections 43.3. Aircraft certificated under part 91 shall perform and document maintenance in accordance with 14 CFR part 91, subpart E.