TM 10-6640-239-13 1-10 1-10.    LOCATION AND DESCRIPTION OF MAJOR COMPONENTS. NOTE Van  exterior  sides  and  interior  walls  are  designated  "curbside"  (right)  and "roadside" (left) when viewed from the rear of the van. a. Rear and Curbside Exterior.  (Refer to Figure 1-2.) Purge Intake Door (1):  Hinged, double latched access door for purge intake damper.  Purge Intake Door shall be open during purge cycle to allow environmental control unit to ventilate the laboratory. Mechanical Room Entrance Door (2):  Provides the only entrance/exit for mechanical room.  Provided with an internal door lock release mechanism to facilitate an emergency exit. Laboratory Entrance Door (3):  Primary entry/exit for laboratory section of trailer.  Provided with an internal door lock release mechanism to facilitate an emergency exit. Purge Exhaust Door (4):  Hinged, double latched access door for purge exhaust damper.  Purge Exhaust Door shall be open during purge cycle to allow air to be exhausted from laboratory. Rear Door (5):  Primarily used to load and unload overpack boxes.  Provides a secondary entrance/exit for laboratory.  Provided with an internal door lock release mechanism to facilitate emergency exit. Sink Drain Connection (6):  Located under the trailer, the sink drain connection provides a means of connecting a drain hose to sink drain. Curbside Storage Box (7):  Provides storage area for miscellaneous equipment.  Provided with fork truck lift slots and retaining pins for removal/installation.  Provides storage area for power input cable that connects power distribution module to power source. Trailer Accessories Storage Door (8):  Provides access to storage area for trailer accessories; i.e., roadside reflectors, wheel chocks, various tools, wiping rags, etc. Bridge Platform (9):  Provides a platform to connect Mod Lab A to Mod Lab B. 5 3 7 8 2 1 4 6 MBPLB-1-2B 9 Figure 1-2.  Rear and Curbside Exterior