Abuilding is said to be suffering from sick building syndrome (sbs) when what percentage of the occupants complain of a general array of symptoms that abate after leaving the building?

20%.

Explanation:

SBS (Sick Building Syndrome) may be defined as the medical condition in which most of the individual of the building shows symptoms of illness without unknown reason.

Any building to be categorized as SBS require the some percentage of the individuals should show the symptom. This percentage is atleast 20% of the occupants of the building. These symptoms might gone away after the people leave the building.

Thus, the answer is 20 %.