Both the Petroleum Safety Authority Norway (PSA) and the Norwegian Labour Inspection Authority gave emphasis in 2022 to the risk associated with exposure to carcinogenic chemicals.
The national occupational exposure limit for benzene was reduced by 80 per cent in 2021, and a further 50 per cent cut is expected within the next few years. A new limit for diesel exhaust fumes also came into effect for the petroleum sector in February 2023.
Managing the benzene exposure risk has long been a concern at the PSA. This continued in 2022, when increased attention was also given to other carcinogenic agents – diesel exhaust gases, asbestos, α-quartz, welding fumes, formaldehyde, low-activity radioactive (LAR) scale and so forth. Such substances are followed up both through audits of individual companies and by information acquisition and the accumulation of knowledge.
In the summer of 2022, the PSA acquired information from players in the industry on their management of risk associated with the use of carcinogenic chemicals. Among other matters, they were asked to account for the amounts of such materials they were using, which of them might be released through work operations and processes, which groups of personnel could be exposed, and what systems had been established to manage the exposure risk.
They were also requested to identify the three carcinogenic chemical agents considered to posed the highest exposure risk, with benzene and diesel fumes named by most companies. But such components as asbestos, welding fumes, α-quartz and formaldehyde were also mentioned.
The report from this survey is due to be published during the first half of 2023. Information specifically related to benzene exposure from handling drilling mud and diesel exhaust fumes was also obtained.
Diesel exhaust
Diesel exhaust fumes have been classified as carcinogenic by the International Agency for Research on Cancer (IARC) since 2012, but no occupational exposure limit for this pollutant had previously been set in Norway. As mentioned above, such a limit – measured as elemental carbon – has now been introduced for the petroleum sector.
The carcinogenic properties of diesel exhaust largely relate to the particles in the fumes, which is why elemental carbon has been chosen as the marker for the particle phase.
In this connection, a joint project was launched in 2022 with Norway’s National Institute for Occupational Health (Stami) on diesel exposure in the petroleum sector. This aimed to:
- identify to what extent diesel exhaust fumes represent a challenge
- map how the companies manage the risk
- acquire and collate existing knowledge
- assess available techniques for measuring elemental carbon.
The outcome was a report on diesel exhaust fumes as a working environment factor in the petroleum industry, which rested in part on data acquired from the industry. Results and conclusions from the project were presented at a seminar staged by the PSA in December 2022, with the full report published in February 2022.
Findings from the project showed that these fumes represent a substantial working environment challenge, affecting a broad range of employees. But the information acquired indicated that a number of companies have established or are in the process of establishing systems for managing the risk.
While a number of companies also identified technical and operational measures taken to reduce the risk, the report pointed to knowledge gaps and risk management deficiencies related primarily to ignorance about exposure levels for elemental carbon.
Measurements of this substance in the petroleum industry have been very limited in extent. Those performed have largely involved static area monitoring, while person-borne exposure monitoring is absent.
This means that no adequate overview of exposure levels for elemental carbon is available, nor information on which circumstances and under which conditions diesel exhaust fumes could represent an exposure risk. The basis for establishing appropriate management systems and for identifying and prioritising risk-reducing measures is therefore inadequate.
Effects and further work
The knowledge acquired through the work on carcinogenic chemicals provides the basis for developing risk pictures as well as purposeful and risk-based follow-up in the industry.
These substances will remain a priority technical issue in 2023, including a particular concentration on formaldehyde and LAR scale in addition to benzene and diesel exhaust fumes. The project on these fumes is continuing in 2023, with the emphasis on learning more through occupational hygiene measurements on facilities and at land plants.
This article is taken from PSA's annual report for 2022. The full report (in Norwegian only) can be read here.