In one of our latest project we have been appointed by HMRC to evaluate occupational exposure of traffic officers to various contaminants associated with fuel testing and vehicle diesel exhaust fumes. The officers carry out routine check of diesel fuels throughout the United Kingdom. In the course of their duties the officers can get exposed to various chemical contaminates. Our task was to evaluate this exposure with a particular emphasis on diesel fumes.
Burning of diesel fuel results in a release of large quantity of contaminants. They can range from simple hydrocarbons such as benzene to more complex polyaromatic hydrocarbons (PHA’s) . In addition to these highly hazardous compounds the combustion process liberates water vapours, Carbon dioxide, Carbon monoxide and range of Nitrogen oxides.
Many of the compounds released during burning of hydrocarbons are associated with cancer and often cause short irritation of the respiratory tract and eyes. Prolonged exposure to diesel exhaust fumes, in particular to any blue or black smoke, could lead to coughing, chestiness and breathlessness. There is some evidence that repeated exposure to diesel fumes over a period of about 20 years may increase the risk of lung cancer. As diesel exhaust fumes have not a specifically assigned exposure levels it is necessary to sample and analyse some of the most harmful constitutes of the diesel exhaust fumes. Typically, it is necessary to monitor the simple gases such as carbon monoxide, carbon dioxide and the nitrogen oxides. In addition to these it is also necessary to evaluate the level of carbon based materials the operatives are exposure to.
Combustion of the fuel produces significant quantities of exhaust smoke. The visual characteristics of this escaping smoke can also be used for detection of mechanical fault with the engine. If the vehicle produces mainly blue smoke it is likely that the fuels is not adequately burned and the diesel exhaust fumes are full of oil aerosol. If the generated smoke is dark it is likely to be consisting mainly from sooth, oil and unburned fuel. White smoke on the other hand indicates presence of water in the fuel. Regardless of the nature of the smoke all exhaust emission are full for diesel fumes and other harmful substances.
During this project, we have fitted the enforcing officers with specialist samplers for the assessment of diesel exhaust fumes as well as samplers for evaluation of fuel vapours and some specialist chemical used in fuels detection.
The officers are often engaged in situation where they need to quickly assess whether fuel used in the vehicles or sold at the petrol station is genuine. They use a variety of tools to tell them if the fuel is contaminated or genuine. Our assessment of all the activities performed by the offices showed that their personal exposure levels to various contaminates we low and well controlled.