Volatile organic compounds (VOCs) can be of natural or anthropogenic origin
and can affect human health, air quality, and materials and objects located in spaces with
elevated VOC concentrations. In my thesis, I measured total VOC concentrations in
selected faculty spaces using a sensor, and determined the concentrations of acetic acid,
formic acid, and NO2 in the air using passive samplers and ion chromatography. For
measuring total VOCs in the air, I used the VOC-TRAQ II sensor. This is a sensor with
a photoionization detector (PID) that uses UV light to ionize gas molecules with low
ionization energy. The ionized molecules create an electric current proportional to the gas
concentration. PIDs are non-selective and are used to measure total volatile organic
compounds (TVOC), but do not detect the main components of air. To determine the
concentration of acetic acid, formic acid, and NO2, I sampled the air using SKC UMEx
200 passive samplers. The samplers consist of a polypropylene housing covering two
reactive strips treated with triethanolamine (TEA), measuring 2 cm x 2 cm. TEA very
effectively retains the acidic analytes under study. I performed extraction from the strips
and determined acetate, formate, and nitrite ions using ion chromatography. I calculated
the results into concentrations of analytes in the air, then compared the results obtained
by both methods. The measurement results showed that the concentrations of volatile
organic compounds in most rooms are relatively low, indicating adequate ventilation and
proper handling of chemicals. The highest concentrations were measured in the laboratory
with high activity and in the rooms with books. The comparison of both methods revealed
that volatile organic acids represent a significant, but not dominant, portion of the total
volatile organic compounds in the investigated spaces.
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