TM 3-1040-280-20&P APPENDIX B MAINTENANCE ALLOCATION CHART Section I.  INTRODUCTION B-1. THE ARMY MAINTENANCE SYSTEM MAC. a. This  introduction  (section  1)  provides  a  general explanation   of   all   maintenance   and   repair   functions authorized   at   various   maintenance   levels   under   the standard Army Maintenance System concept. b. The   Maintenance   Allocation   Chart   (MAC)   in section II designates overall authority and responsibility for  the  performance  of  maintenance  functions  on  the identified  end  item  or  component.    The  application  of the maintenance functions to the end item or component will be consistent with the capacities and capabilities of the designated maintenance levels, which are shown on the MAC in column (4) as: UNIT, which   includes   two   subcolumns,   C   (operator/ crew) and O (unit maintenance) INTERMEDIATE, which  includes  two  subcolumns,  F (Intermediate Direct Support) and H (Intermediate General Support) DEPOT, which includes a D (Depot) subcolumn c. Section   III   lists   the   tools   and   test   equipment (both  special  tools  and  common  tool  sets)  required  for each  maintenance  function  as  referenced  from  section II. d. Section   IV   contains   supplemental   instructions and   explanatory   notes   for   a   particular   maintenance function. B-2. MAINTENANCE   FUNCTIONS .        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 (e.g., by sight, sound, or feel). b. Test.  To verify serviceability by measuring the mechanical, pneumatic, hydraulic, 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 (includes decontaminate, when required), to preserve, to drain, to paint, or to replenish fuel, lubricants, chemical fluids, or gases. d. Adjust.          To     maintain     or     regulate,     within prescribed    limits,    by    bringing    into    proper    or    exact position,  or  by  setting  the  operating  characteristics  to 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 compared. g. Remove/install.  To remove and install the same item    when    required    to    perform    service    or    other maintenance   functions.      Install   may   be   the   act   of emplacing, seating, or fixing into position a spare, repair part, or module (component or assembly) in a manner to allow the proper functioning of an equipment or system. h. Replace.  To remove an unserviceable item and install a serviceable counterpart in its place.  "Replace" is   authorized   by   the   MAC   and   is   shown   as   the   3d position code of the SMR code. i. Repair. The application of maintenance services including fault location/ troubleshooting, removal/ installation, and disassembly/assembly procedures, and maintenance actions to identify troubles and   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. B-1