When maintaining radioactively illuminated fire control equipment, follow radiation
hazard procedures in warning summary.
General support maintenance instructions for the M18 quadrant cover assembly are
identical to the M17 quadrant cover assembly.
1 fc 1 7 3
1 fc 1 7 2
To avoid injury to personnel and damage to equipment, cover assembly will only be
removed if counters are fully illuminated. Place cover assembly in secure area and
exercise caution to avoid breakage of nuclear lamps.
Remove seven machine screws (1), seven lockwashers (2), cover assembly (3), and O-ring (4) from housing
assembly (5). Discard lockwashers and O-ring.
Exercise special care when removing optical instrument windows to ensure that
tritium vials are not damaged.