Background. A health certificate is required to work on the offshore petroleum installations of
the Norwegian Shelf. Loss of health certificate (loss of licence, LOL) may cause economic
problems for the individual worker. A private compensation system (OSO) was established for
Norwegian offshore workers in 2002, comprising 8000–11,000 individual members of workers
organisations: approximately one third of the population offshore. This study aims at describing
the reasons for compensation of offshore workers who have lost their certificates.
Materials and methods. Of 595 workers who applied for compensation in the period 2002–2010, 38 declined to participate in the study. Of the remaining 557, 507 were granted and 50
were denied compensation. All medical records held by the scheme concerning the 507 compensated
applicants were examined. Health data were systematically extracted, analysed, and
compared with general population statistics.
Results. Musculoskeletal conditions were the most frequent conditions causing LOL for both
sexes (42.5%), followed by psychiatric, neurological, and malignant diseases for women, and
cardiovascular (19%), neurological, and psychiatric conditions for men. Musculoskeletal disorders
were more prevalent than in the general population, and the prevalence of knee problems
was particularly high. Among malignant diseases we found a high proportion of brain tumours
and renal cancer. The causes are unknown and warrant further investigation in this population.
Among women granted compensation, 78% were catering workers, while 50% of the men were
process workers, reflecting the gender distribution in these working groups.
Conclusions. Musculoskeletal conditions were the most frequent cause of application for LOL
compensation for both sexes, followed by psychiatric, neurological, and malignant diseases for
women, and cardiovascular, neurological, and psychiatric conditions for men. The cause of the
higher incidence of musculoskeletal diseases, brain tumours, and renal cancer found in this
study compared to the general population warrants further investigation
