Synthetic mineral fibres (i.e. man-made vitreous fibres, MMVF) are classified into glass filament, mineral wool (glass wool, rock wool and slag wool), refractory ceramic fibres, and fibres for special purposes. This paper analyses the data on occupational irritant contact dermatitis (ICD) caused by MMVF during 1990-99 in Finland according to the Finnish Register of Occupational Diseases (FROD). A total of 63 cases from MMVF were reported. 56 were diagnosed as ICD, and 2 as allergic contact dermatitis, both from rock wool. 53 out of 63 cases were due to mineral wool or glass filaments; half of the cases, according to a rough estimate, were due to mineral wool and a half due to glass filaments used in lamination work. Carpenters, building workers and insulation workers have the highest risk of ICD from mineral wool. 4 cases in carpenters, 4 in building workers and 2 in insulation workers were reported from MMVF. For every 100 000 employed workers, only 1.6 cases of ICD in carpenters, 2.7 in building workers and 9.1 in insulation workers were annually due to MMVF, respectively. Mineral wool used in construction work, insulation, etc., cannot be considered to be a common cause of occupationally induced ICD. However, information on harmful skin effects of MMVF is useful to exposed persons in the prevention of the effects.