The safety requirements for APCS of the international standard IEC 61508 "Functional safety of electrical, electronic, programmable electronic systems related to safety" are discussed in detail, their interpretation for practical implementation is given. The specific steps required to obtain an IEC 61508 certificate of conformity have been successively disclosed. Particular attention is paid to preparation for certification, including the definition of the certification object, project infrastructure, plan and cost estimate for the work. The requirements of the standard related to safety management are considered, methods for its quantitative assessment and measures to ensure it are proposed. The issues of FPGA certification and the application of the Assurance Case methodology are discussed separately. A set of exercises is given to consolidate skills in the field of ensuring and assessing functional safety.