Loss of health certificates among offshore petroleum workers on the Norwegian Continental Shelf 2002-2010.

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.