Caught an article on CleanLink (also on SchoolFacilities.com) quoting Dr. Marilyn Black, founder of Greenguard Environmental Institute (GEI) titled "A Green Building is Different Than a Healthy Building".

Dr. Black points out that building components and finishes, and office equipment, may be friendly to the environment, but still off-gas a wide array of chemicals, such as formaldehyde, that are not particularly people-friendly.  All true.

Note, however, that as the building and its contents age, less and less chemical is off-gassed (one might say that the gas has all been "outed"), so indoor air quality concerns ought focus on airborne particles, not gasses - bacteria, spores & pollen, dust mite droppings, etc.  An inadequately cleaned building will accumulate fine particles, mostly in the carpet; foot traffic and air circulation will keep some of those particles airborne; and, as particles accumulate, the building will become progressively less healthy for the people breathing its air.

One can counter this trend by proper cleaning: HEPA filters on the vacuums, vacuuming rather than dust mopping hard floors, microfiber wiping rather than feather-dusting, and microfiber damp mops rather than traditional string mops.  One can also measure indoor air quality (airborne particle count) ongoing, to monitor the effectiveness of one's program, and for the edification of one's clients.

Easy and inexpensive to do, and a great way to keep your green building (or even your off-color one) healthy for staff, and for the "breathing public".