Official statistics show that labor activity is accompanied by the presence of various kinds of hazards and harmful working conditions, which are risk factors for injury and the development of occupational diseases of workers. Risk assessment is one of the necessary procedures of the occupational health and safety management system and includes the following stages: identification of all risk-forming factors characteristic of the organisation, compilation of a unified register of hazards, calculation of occupational risks and development of measures to reduce their impact in the workplace. With all the diversity of hazards, there is no unified approach to the development of the organisation's register, and this is an urgent problem, the solution of which will allow a qualitative approach to the issue of calculating and assessing professional risks. The article offers an accessible and practical-oriented method for identifying and developing a unified register of hazards of an organisation, which allows setting the uncertainty parameter of the register, which is an additional coefficient when calculating occupational risk in the workplace.