This credit requires compliance with a varied group of items that cumulatively help keep pollutants out of the indoor air. These requirements include self-closing doors on janitors' closets, MERV 13 filtration on mechanical equipment, and entryway trackoff systems.

Compliance will require the coordination of team members—including the mechanical engineer, architect, plumbing engineer, and contractor—and also impact project design and operations. The basic requirements are:

• Permanent entryway walk-off systems at least 10 feet long (up from 6 feet in previous versions of LEED) at all regularly used, exterior-to-interior entrances and entrances from covered parking garages. (Roll-out mats are acceptable only if maintained on a weekly basis.) 
• Designated exhaust of all hazardous gas and chemical use areas—including garages, housekeeping, janitors’ closets, laundry areas, science labs, art rooms, workshops, copy and printing rooms, and prep rooms.
• An exhaust rate of 0.5 CFM/SF, with no air recirculation, in hazardous gas and chemical use areas.
• Self-closing doors on all spaces outlined above.
• Deck-to-deck partitions or hard-lid ceilings on all spaces outlined above.
• MERV 13 filtration for each ventilation system serving regularly occupied spaces with outdoor air.