The pressure equalizing pad, 88 542-951, is attached to a holder that is attached to the inner mask plate.

1. Check that the holder for the pressure equalizing pad is not deformed. If it needs replacing: send the full face mask to authorised maintenance staff.
2. Fit the rubber pressure equalizing pad. The pressure equalizing pad has four slots, and the holder must pass through one of these. Make sure the holder runs properly through the slot so that the pressure equalizing pad does not loosen or is shifted out of position.