Aim: To examine the quality of manual job coding carried out by occupational health teams with access to a software application that provides assistance in job and business sector coding (CAPS).Methods: Data from a study conducted in an Occupational Health Service were used to examine the first-level coding of 1,495 jobs by occupational health teams according to the French job classification entitled “PSC- Professions and socio-professional categories” (INSEE, 2003 version). A second level of coding was also performed by an experienced coder and the first and second level codes were compared. Agreement between the two coding systems was studied using the kappa coefficient (?) and frequencies were compared by Chi2 tests.Results: Missing data or incorrect codes were observed for 14.5% of social groups (1 digit) and 25.7% of job codes (4 digits). While agreement between the first two levels of PCS 2003 appeared to be satisfactory (?=0.73 and ?=0.75), imbalances in reassignment flows were effectively noted. The divergent job code rate was 48.2%. Variation in the frequency of socio-occupational variables was as high as 8.6% after correcting for missing data and divergent codes.Conclusions: Compared with other studies, the use of the CAPS tool appeared to provide effective coding assistance. However, our results indicate that job coding based on PSC 2003 should be conducted using ancillary data by personnel trained in the use of this tool.