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This study measured and analysed individual volatile organic compounds (VOCs), total hydrocarbon and total VOCs at an oil refinery. Measurements were taken at various workplace locations, of the ambient air and at some off-site facilities such as its gantry terminals, ETP and tank farms. The study also identified certain pollutants that are difficult to measure routinely but could give an indication of their presence in a refinery. The VOCs were sampled using charcoal adsorption tubes and desorbed using a thermal desorption technique. The samples were subsequently analysed by Varian 2200 GC/ MS system. The 8-h average concentrations of benzene, toluene, ethylbenzene and xylenes ranged between 23. 48-113.05, 18.70-72.54, 2.91-9.80 and 5.83-27.64 µg/m 3 , respectively. Alongside substituted benzenes, such as 135 and 124, trimethylbenzenes and naphthalene were also detected. The total hydrocarbon ranged between 5.0-13.8 ppm and the NMHC was in the range of 2.2-9.0 ppm. The study indicates the concentration of fugitive emissions of VOCs in the refinery and its utilities.

A comprehensive environmental noise exposure study was carried out in and around a major iron and steel works. The works was located in the central part of the city and was surrounded by residential, commercial, and sensitive receptors. Traffic activity near the plant was significant and added to the background noise level. Considering the variety of noise sources in the plant area and in the neighborhood, a practical approach to measure noise equivalent level in the plant and in the residential, commercial, industrial, and silence zone was adopted. A modular precision integrating sound level meter with statistical analyzer module, octave filter set, and calibrator were used during the measurements. The day and night level, Ldn, was determined. Worker exposure was assessed by determining the speech interference level (SIL), loudness level, and noise rating level at one of the major sources located in the power plant of the steel works. The results indicate that SIL was 94 dBA, loudness level was 112 phons, and the noise rating was in the range of 85-95. A traffic noise index also was determined near the works gates and was in the range of 68-96. The impact on the community is significant as observed from Ldn levels. Some mitigation measures for noise control are also discussed.

Herein, we reported our studies related to structural elucidation and gas-phase fragmentation patterns of the imidazolium and pyridinium based ionic liquids, using a positive ion electrospray ionization triple quadrupole mass spectrometry. Ionic liquids mainly imidazolium/ pyridinium/alkylammonium salts, possess properties due to which there are many applications from the point of view of green chemistry. The recorded mass spectral patterns are presented and possible pathways for fragmentations are suggested. The mass spectrum of tetrabutylammonium bromide and its fragmentation pattern is discussed since we used this compound as a template in the synthesis of ionic liquids. Our analysis also suggests possibilities of associations of ions in the form of C2A + species in vapour phase for the studied ionic liquids.