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 NO$_2$ 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 NO$_2$, 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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