The Brazilian standard ABNT NBR ISO 13849 brings safety requirements and guidance about design principles and integration of safety-related parts of control systems (SRP/CS), including the design of software. For these parts of the SRP/CS, it specifies characteristics that include the performance level required for carrying out safety functions. ABNT NBR 13849 applies to SRP/CS for high demand and continuous mode, regardless of the type of technology and energy used (electrical, hydraulic, pneumatic, mechanical, etc.), for all kinds of machinery.