Maintenance, repairs, modifications, or construction performed upon aircraft not addressed elsewhere in this code shall be conducted in accordance with NFPA 410.
Maintenance of
aircraft fuel systems shall comply with Sections 2004.8.1
through 2004.8.6.
Any person conducting
aircraft servicing, maintenance, or testing of the fuel system
using the air ventilation procedures, shall reduce the
fuel tank atmosphere to below 20 percent of the lower
flammable limit of the fuel vapors. Air ventilation, as used
herein, means to pass undiluted air (air not containing
flammable vapors) through an aircraft fuel tank to render
the atmosphere of the tank below the lower flammable
limit of the fuel vapors involved. Before any inspection or
work is performed, tests by a qualified person shall be
conducted to determine that the presence of flammable
vapors in or around the fuel tank does not constitute a fire
or explosion hazard. This condition shall be maintained
throughout the period of inspection or work.
All open flame and spark producing
devices within flammable vapor areas shall be shut down and
shall not be operated while air ventilation is occurring.
Electrical equipment used in
the flammable vapor areas shall be approved for use in Class
I, Group D, Division 1 Hazardous Locations, as defined in
Chapter 9 of the LAMC (Electrical Code).
Aircraft electrical circuits which
are in flammable vapor areas shall be de-energized.
Suitable warning signs shall be
placed in conspicuous locations around the aircraft to indicate
that tank ventilation is in progress.