Source of organics in the air of an office building.

The inventory of organics in the air of a ten year old office building shows a wide variety of natural and synthetical volatile organic compounds (VOCs). Although 240 employees consume 1200 - 1500 cigarettes per day, the effective ventilation system reduces the ETS rapidly, however, aromatic hydrocarbons and some natural compounds still remain in the air in the higher μg/m3-range. Systematic analyses of volatile compounds of all cleansers used shows that they are sources of higher limonene amounts. Aromatics entered by way of "fresh air'' intake near the parking entrance at street level. The time depending concentration of the indoor air clearly showed maximums during the main arrival and departure times of cars (without catalytic converters). The substitution of the cleansers and modifying the fresh air intake reduced the indoor concentration of VOCs significantly.