This appendix provides a summary of the maintenance operations for MK12 Surface Supported Diving System. It
authorizes levels of maintenance for specific maintenance functions on repairable items and components and the tools
and equipment required to perform each function. This appendix may be used as an aid in planning maintenance
B-2. Maintenance Functions
Diving Air Compressor
Maintenance functions will be limited to and defined as follows:
a. Inspect. To determine the serviceability of an item by comparing its physical, mechanical, and/or electrical
characteristics with established standards through examination.
b. Test. To verify serviceability and to detect incipient failure by measuring the mechanical or electrical
characteristics of an item and comparing those characteristics with prescribed standards.
c. Service. Operations required periodically to keep an item in proper operating condition, i.e., to clean
(decontaminate), to preserve, to drain, to paint, or to replenish fuel, lubricants, hydraulic fluids, or compressed air
d. Adjust. To maintain, within prescribed limits, by bringing into proper or exact position, or by setting the
operating characteristics to the specified parameters.
e. Aline. To adjust specified variable elements of an item to bring about optimum or desired performance.
f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test measuring
and diagnostic equipments used in precision measurement. Consists of comparisons of two instruments, one of which is
a certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the instrument being
g. Install. The act of emplacing, seating, or fixing into position an item, part, module (component or assembly)
in a manner to allow the proper functioning of the equipment or system.
h. Replace. The act of substituting a serviceable like type part, subassembly, or module (component or
assembly) for an unserviceable counterpart.
i. Repair. The application of maintenance services (inspect, test, service, adjust, align, calibrate, replace) or
other maintenance actions (welding, grinding, riveting, straightening, facing, remachining, or resurfacing) to restore
serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly, module
(component or assembly), end item, or system.