Complex study of health state covered 666 workers of gas transport enterprise situated in Far North of Russian Federation, revealed risk factors of neurosensory deafness. Neurosensory deafness risk depends on intensity of occupational noise and length of service under exposure to noise, on worker's age, presence of arterial hypertension and type of lipid metabolism disorders. The study found no correlation between neurosensory deafness risk and duration of residence in Far North. The authors suggested a mathematic model to evaluate risk of neurosensory deafness.