Safety is a major focus when operating machines and systems. No matter how good a machine or system is, if its safety is not guaranteed, it cannot be used with peace of mind. Safety standards have been introduced as a means of ensuring safety. In recent years, exports and imports of machinery and systems have been flourishing, so safety standards are not only applicable within one's own country, but a common international standard is required. Therefore, the international standards such as ISO and IEC standards were established. This time, we will introduce the system of such international standards.
ISO standards and IEC standards, which are international standards
International safety standards for machines and systems include ISO standards and IEC standards. The two standards cover different fields.
The official name of ISO is the International Organization for Standardization, and it is an international standardization organization for all industrial fields except electrical, communication and electronic technology fields. These international standards are called ISO standards. It was launched in 1947 and now has approximately 160 participating countries.
On the other hand, IEC, whose official name is the International Electrotechnical Commission, is an international standardization body for electrical and electronic technology. These international standards are called IEC standards. It was launched in 1906 and now has approximately 80 participating countries.
In the industrial field, the ISO standards are for mechanical systems, and the IEC standards are for electrical systems.
ISO and IEC are separate bodies that establish the standards necessary for their respective fields. However, such standards are not defined for individual machines and systems. Since machines and systems are constantly evolving, it is impossible to respond individually. That is why ISO/IEC Guide 51 was established. ISO/IEC Guide 51 divides the ISO/IEC standards into three layers, and by combining them, it is possible to support all kinds of products
Three standards in ISO/IEC Guide 51
As mentioned above, ISO/IEC Guide 51 classifies each standard into three layers. The classification is as follows.
A standard
A standards are called basic safety standards, and are defined as "standards that deal with basic concepts and design principles that can be used in common by all machinery." It used to consist of three ISO standards, but now it consists only of ISO12100:2010, which combines them into one.
B standard
B standards are called group safety standards and are defined as "standards that deal with safety or safety devices that can be used in a wide range of machinery". Both the ISO and IEC standards include many standards in the B standard. Part: General Requirements (IEC60204-1)”.
C standard
C standards are called individual machine safety standards, and are defined as "standards that prescribe detailed safety requirements for specific machines." Unlike the other two standards, which cover a wide range, this C standard is detailed for each type of machine. As with the B standard, both the ISO standard and the IEC standard include many standards.
As mentioned above, the A standard, B standard, and C standard each have a different range of coverage. Since the A standard has the widest range and the C standard has the narrowest range, in principle, the B standard is stipulated based on the requirements of the A standard, and the C standard is stipulated based on the requirements of the A and B standards. increase. Therefore, when determining the applicable standards in the design of machinery, if there is an applicable C standard, it alone can satisfy the safety standards. However, as introduced in the previous section, machines and systems are progressing day by day, and it is not uncommon for cases where there is no applicable C standard or cases where the applicable scope of the existing C standard is exceeded. In order to ensure safety in such cases, it is important to conduct safety evaluations based on the requirements of A and B standards.