Offshore personnel exposed to these fumes report health problems such as nausea, dizziness and headaches.
PSA audits have registered nonconformities from the requirements set in this are, and it has received several whistleblowing reports.
Gas and particles
Diesel engine exhausts comprise a mix of gases, with nitrogen dioxide and carbon monoxide as the commonest components, plus particles consisting of carbon bearing various chemicals hazardous to health – including polycyclic aromatic hydrocarbons (PAH), sulphur, nitrates and metals.
Although these particles are very small, they collectively have a large surface area. When breathed in, they are carried deep into lung tissue and may have such effects as damaging genetic material or creating inflammatory reactions which could play a role in developing cancer.
Diesel fumes are classified as carcinogenic for humans by the International Agency for Research on Cancer (IARC). In Norway, the National Institute for Occupational Health (Stami) has helped to increase knowledge of the health effects of exhaust fumes while also mapping exposure.
Regulatory requirements
The PSA has observed that uncertainty prevails on many facilities about how diesel exhaust fumes should be dealt with, particularly when weather conditions create acute problems.
According to the regulations, decisions must be based on qualified mapping and risk analysis. Placing responsibility on the individual employee over doing work in exhaust-polluted areas is contrary to the regulatory requirements.
Read more
Section 18 of the management regulations on working environment analysis
Section 33 of the activities regulations on organisation of work
Section 36 of the activities regulations on chemical health hazard
Such pollution can be reduced in most cases by implementing simple technical measures.
The PSA expects the companies to keep abreast of knowledge advances and changes to the regulations, and preferably to collaborate in order to develop good practice in dealing with exposure to exhaust fumes.
Challenging to measure
Only limited information is available about how high the concentration of diesel exhaust on offshore installations can get. That partly reflects the challenges faced in carrying out measurements.
Limit values exist for some of the chemicals in the fumes, such as carbon monoxide, nitrogen oxide, organic compounds like PAHs, benzene and formaldehyde.
Work is under way to establish limit values in Norway for particles from diesel exhaust in the atmosphere, and these are due to be in place early next year. A method for measuring such particles has also been developed.
Sources
Diesel exhaust fumes derive from a number of sources, with the main power generators on mobile facilities a major contributor. And diesel-driven forklifts, cranes, cement units, fire pumps and emergency generators can have substantial local significance.
So can permanent and temporary diesel power units, while exhaust fumes from supply ships will also contribute to exposure.
Weather
Typically, exposure to exhaust fumes occurs in calm weather. They can be spread from diesel engines to working and accommodation areas on the facilities.
Over time, conversion of both equipment and facilities to electric operation will make a positive contribution to reducing exhaust pollution.