Case Studies
Nuisance odours
Following repeated complaints of odours from a takeaway shop below a flat, the laboratory was requested to investigate. Using tenax tubes and air sampling pumps, an environmental health officer took samples of the atmosphere within the flat and sent them to the public analyst, who did a detailed analysis by gas chromatography using thermal desorption and mass spectrometry.
Following repeated complaints of odours from a takeaway shop below a flat, the laboratory was requested to investigate. Using tenax tubes and air sampling pumps, an environmental health officer took samples of the atmosphere within the flat and sent them to the public analyst, who did a detailed analysis by gas chromatography using thermal desorption and mass spectrometry. The analyst detected many food-related volatile organic compounds, the profiles of which closely matched the atmosphere in the shop. As part of the investigation, the analyst did real-time carbon monoxide and carbon dioxide monitoring to assess whether combustion gases from the gas cookers featured in the atmosphere in the upstairs flat (see Fig).
The results revealed significant levels of carbon monoxide in the flat, which was particularly alarming since the residents included a two-year old child. Furthermore, the pattern of peaks revealed that combustion gases – CO2 and CO – were present when the shop opened and disappeared when it closed.
The analyst requested a detailed ventilation assessment of the shop which revealed that the extraction system used in the shop kitchen was inadequate. Furthermore, the pots used on the cookers were far too big, changing the burning characteristics of the gas-fired rings and resulting in elevated levels of carbon monoxide. What turned out to be an investigation based on nuisance (odours) had become far more serious with regards to health and safety of the people in the flat above and the staff working in the kitchen.
A notice was served on the shop and following detailed remedial works and further monitoring, the problem was resolved. However, as a result of a number of other indoor air investigations in similar properties above takeaway shops, it became apparent that this was not an isolated case and odour complaints in these situations are now accompanied by combustion gas assessments.
