(Special Interview) In Pursuit of Sustainable Production Safety

The number of products recalled by companies is too great to count. The incidence of major accidents on the production floor (involving the injury or death of three or more people in a single accident) were decreasing in the 1970s and 80s, but are on the incline today (see graph). Even Japan, which is one of the leading manufacturing countries of the world and is well trusted both domestically and internationally, has no claim on safety.

The level of maturity in a society's safety culture can be seen in the degree of safety that it pursues. In the age when safety culture was still at an early stage of development, companies felt that it would be cheaper to simply warn users to be careful in the use of products rather than to actually spend money to provide the machines and other hardware needed to manufacture truly safe products. In other words, the responsibility for ensuring safety was in the hands of the users, who were in danger if they didn't follow the operating instructions to the letter, rather than being in the hands of the designers and manufacturers. In this scenario, accidents were due to improper use and carelessness. From the users' standpoint, however, this way of thinking was completely unacceptable. Even though they were being told that accidents would not happen if products were used in the normal manner, they could not accept the fact that faults or accidents may occur even with the lowest possible probability. In the age of lifetime employment, employees had a strong sense of loyalty to the company, and even if they were injured in an industrial accident, they were likely to say that it was due to their own carelessness. It could be that in a situation where employees did not express their rights, it was difficult to raise the level of safety.

In Europe, where the safety culture preceded that of Japan, the approach taken was to make the hardware elements as safe as possible, and then to show the remaining dangers to users in an easy-to-understand way, so that users would exercise caution. By doing this, they met their responsibility to explain the situation to users, and clarified the division of the roles.

To achieve safety, we need to establish clear guidelines that tell us exactly what it is. After all, machines break, and people make mistakes. Safety is a goal, but it will never be completely achieved. Accordingly, various international standards define safety as "Freedom from unacceptable risk." Quantitative concepts are also introduced that define risk as a combination of the probability of a hazard occurring and the degree of the resulting hazard, with the proviso that it is never zero. As a result, manufacturers, administrators, and users accept this as fact and agree to use what is essentially an international consensus, which forms the basis of the ISO (International Standards Organization)/IEC (International Electrotechnical Commission) Guide 51 (see description elsewhere).

The Robens Report (1972) from the U.K. could be called the beginning of international safety standards. At the time in the U.K., attempts to provide safety consisted of standards based on mandatory regulations for each type of machine in use. However, each time an accident occurred, a new regulation was created, with the result that safety measures were randomly patched together and it became increasingly difficult to respond to the needs of the day. Recognizing that there were limits to what laws and regulations could do by themselves, a new concept took hold in which both manufacturers and users autonomously responded. The basic items, such as the responsibilities of the enterprise owners, manufacturers, and users, were set down in laws, while concrete matters were covered by various rules. Instead of deciding minimum levels through structural standards, as was previously being done for the standards of each machine, people began to think that standards should be instituted that would allow the highest possible levels of performance that were achievable at the time.

This is the three-layered structure of international safety standards (see figure). In other words, the three layers consist of type A standards (basic safety standards) that lay down basic concepts and design principles that are common to all types of machines, type B standards (group safety standards) that apply to a wide range of machines, and type C standards (machine safety standards) that apply to specific machines. The idea is that new products may appear everyday, but even if the C standards that specifically apply to them haven't yet been created, the A and B standards can be immediately applied to their manufacture and use.

The key point in international safety standards is the process of risk assessment that is used to estimate the degree of danger in a machine's design in advance. There is a 3-step method for reducing this risk. The first step is to achieve an intrinsically safe design. For example, if you're designing an automatic revolving door, the structure should be designed so that people will not become caught in the door, and if they do become caught, they will not be seriously injured. The second step is the use of safety devices. Before someone becomes caught in the door, or even after they are caught, the door's motion should be stopped before any injury occurs. And the third step is the supply of information. To cover the risk that still remains even after applying the first and second measures, warning labels and operating manuals should be created to provide information on precautions for using the door.

Companies have long been requested to build safety systems based on risk assessment. With the April 2006 revision to Japan's Industrial Safety and Health Law (Article 28-2), however, companies are now obligated to perform risk assessments, and to take necessary measures based on the results.

For example, in the past, if a new machine were installed in a production line, the manufacturer of the machine would be able to simply tell the new operators something like, "be careful of such-and-such a point" and "carry out such-and-such a training program." Today, though, the user can ask the manufacturer for the risk assessment results. This is a big help in raising the level of safety.

Safety devices are also making steady progress, but there is still plenty of room for improvement. In addition to devices like relay switches that control safety by stopping the line as soon as a fault occurs at the component level, I can see growing business opportunities for strengthening the safety system of entire production lines. Japan has ample potential to take the top position worldwide for this technology.

Safety must first be recognized as having significant corporate value before the safety culture can be elevated. It won't work to use negative incentives, such as creating mandatory regulations that threaten penalties, charging huge sums of money as compensation under product liability laws, or relying on the effects of expensive, large-scale recalls. Positive incentives must be put to work. There is no trade-off between productivity and safety, as both can be attained. By ensuring safety, a factory's operating ratio will rise and profits will result. The company's brand will earn consumer trust. Companies that emphasize safety will attract the interest of investors. And opportunities to operate in world markets will increase. I think it would be excellent if safety brands were able to qualify for insurance discounts, and be covered by a system of tax advantages.

It is also essential that professionals in safety-related technology, such as safety assessors, be trained, and that safety certification businesses be promoted. As part of the flow of deregulation, safety standards could become largely autonomous under private control, as they have in Europe, which would make the role of safety engineers increasingly important.

The academic community also has to support the training of safety engineers. I have long promoted the concept of a "science of safety." I would like to assemble what I call a "safety mandala" (see figure), to classify and organize all of the elements that relate to safety, and systematize safety-related knowledge. As a first step, we will be creating four subject areas -- environment, systems, cities and architecture, and resources and materials -- within a new field of postgraduate study called the Science of Safety at the School of Science and Engineering in Meiji University, starting in spring 2008.

Japan's manufacturing sector must put greater effort into transforming itself into a more sophisticated and advanced field that focuses on safety and reliability. The top management of our manufacturing companies need to commit firmly to this effort, driven by the understanding that, rather than being trade-offs, safety and productivity can both be attained and that, in a very positive way, safety is a core element for every company. This would bring the shine back to Japanese manufacturing, and lead to even greater global strides.

Called "Safety aspects - Guidelines for their inclusion in standards," ISO/IEC Guide 51 was jointly prepared in 1990 by an ISO technical advisory group and an IEC technical committee concerning safety. Many international safety standards have been established based on this guide.

The trend in global safety standards suggests a change from structural (specifications) standards to performance standards. For example, this approach has been taken in the Machinery Directive of the EC Directives. The CE Marking system began with manufacturers voluntarily proclaiming that they had met the requirements of the directive, and attaching the CE Mark. Products without the mark could not be distributed in the European Community. If a manufacturer is not able to prove compliance by itself, or when specific types of machinery are involved, certification is done by a third-party authority. This has led to the basic ISO 12100 and IEC standards for use in the international safety standards of today.

The main point in risk assessment is the introduction of quantitative concepts to estimate risk. The risk assessment procedure outlined in ISO/IEC Guide 51 is as follows. Specify the usage conditions and foreseeable mistakes in usage --> Identify the hazard source --> Estimate the risk --> Evaluate the risk. Then, it must be decided whether the risk is acceptable or not. If it is not acceptable, measures must be taken to reduce the risk, then the assessment procedure must be repeated.

The ISO risk assessment standard is ISO 14121, and the standard for JIS (Japanese Industrial Standards) is JIS B9702. Risk assessment is also included in the Guidelines for Comprehensive Machinery Safety Standards issued by Japan's Ministry of Health, Labor, and Welfare. In addition, the April 2006 revision to Japan's Industrial Safety and Health Law obligates companies to perform risk assessments. As these developments show, risk assessment is continually spreading as a basic concept of safety technology.

The Safety Assessor Certification System was jointly created in 2004 by the Nippon Electric Control Equipment Industries Association (NECA), the Society of Safety Technology and Application, Japan, and the Japan Certification Corporation to train personnel to operate worldwide in the field of design and safety technologies for raising the level of safety in machinery.

There are three qualifications, determined by safety skill level. Designers and managers who are involved in the field of safety attend courses that begin with the subject of risk assessment as the core element of safety development. They proceed to learn the skills that are necessary to evaluate and confirm the adequacy of safety in the kinds of mechanical facilities and production systems that Japanese companies require in today's age of global competition.

Each year, certified assessors must undergo self-surveillance of the risk assessment activities that they have participated in throughout the previous year, and must also renew their certification every two years.