How does ICAO define human factors in Circular 227?

In the 227 advisory circular of ICAO, the definition of human factor is: human factor is a science related to people, including people in working and living environment, the relationship between people and equipment, procedures and surrounding environment, and the relationship between people and others.

Characteristics of human factors:

① Direct or indirect influence of human activities: Human factors are inseparable from human activities. Whether it is the design of tools, the operation of equipment or the writing of programs, it is inseparable from the participation of people. As a part of the system, human actions and decisions will directly or indirectly affect the operation of the system.

People's abilities, defects and needs: Human factors should consider people's abilities, limitations and needs. In the design process, we should ensure that the performance, operation and maintenance of products or systems meet people's abilities and meet people's needs as much as possible.

② Systematization: Human factors not only focus on a single link or a single device, but emphasize the whole system or process. For example, when designing an aviation system, human factors will involve pilots, flight attendants, ground handling and other links, as well as their interaction and cooperation.

The reasons of human factors:

1, bad behavior:

This includes operational errors, violation of regulations, carelessness, and misjudgment. These bad behaviors may lead to accidents or incidents.

Healthy. For example, if the pilot does not check the aircraft system correctly before taking off, it may cause serious problems during the flight.

2. Incorrect operation:

This includes wrong operation steps, wrong operation sequence and improper operation methods. Incorrect operation may lead to serious consequences, such as medical accidents and industrial accidents.

3. Unreasonable design:

If the design of products or systems is unreasonable, it may make it difficult for people to use them correctly, and may even lead to accidents or injuries. For example, if some medical equipment is not designed properly, it may lead to inconvenience or potential safety hazards during use.

4. Management error:

This includes lack of effective training, poor supervision and unreasonable resource allocation. Management errors may affect the operation of the whole system, thus causing accidents or incidents. For example, if the workers in the factory are not adequately trained, they may make mistakes in the operation process, which may lead to industrial accidents.

5. Socio-psychological factors:

This includes work stress, fatigue, mood swings, etc. These factors may affect people's work performance, thus leading to accidents or incidents. For example, long-term working pressure may cause pilots to make mistakes during flight.