What is Risk Assessment?

What can we do to stay "safe"?
Safety measures include creating a system to manage risks (risk management), evaluating the risks inherent in machinery and equipment, and implementing countermeasures according to the results of risk assessment and risk reduction measures (protection measures). )” is required.
Risk assessment is defined as "investigating hazards and hazards," that is, identifying and evaluating occupational hazards, etc., and examining and implementing countermeasures. Article XNUMX) stipulates the implementation of risk assessment as an obligation to make efforts.Especially in modern times, various equipment and substances are used, and hazards and hazards are diversified accordingly. becomes important.

Risk assessment procedure

1. Determining Machine Limitations

Determine specifications such as the range of use of each machine, where it can be placed, and when or how long it can be used.

2. Identifying Hazards

Identify and clarify what hazards are lurking within the scope determined in 1.
Identifying is the act of searching for an attribute in an existing field that relates to a certain subject.
ISO12100 contains a list of hazards, so we search by looking in the section that relates to what we are looking for and checking that hazard list, which is why we call it identification.

3. Risk Estimation

In order to estimate the risk, first determine the risk evaluation elements and evaluation criteria, such as the severity of the harm, the probability of occurrence, and the priority of the risk, and then estimate the risk for each hazard.

Risk assessment elements
judgment factor
Degree of harm
the magnitude of the harm expected from the hazard;
Fatal injury / Serious injury / Minor injury / Slight injury
Definition is possible, but judgment tends to be subjective
Probability of occurrence of harm
Possibility of bodily injury or health injury
Probability of occurrence of hazardous event
Possibility of occurrence of events that may cause harm
Certainly/highly likely/likely/rarely
Definition is possible, but judgment tends to be subjective
frequency of exposure
Frequency of accessing the hazard
Frequently / Occasionally / Occasionally / Rarely
Definition is possible, but judgment tends to be subjective
exposure time
Time of access to hazard
A lot / Somewhat a lot / A little / Almost none
Definition is possible, but judgment tends to be subjective
Possibility of avoiding harm
Possibility of avoiding harm
There are cases that can be defined but are difficult to judge
Four typical risk assessment methods
addition method
A method in which points are assigned to each risk element, the points are added, and the total score is used as the risk evaluation point to determine the risk level.
Accumulation method
A variant of the addition method.

A method of determining the risk level based on the calculated risk evaluation points by setting the points allotment criteria for each risk element, accumulating each point, and calculating the risk evaluation points.
matrix method
A method of determining the risk level by constructing a vertical and horizontal matrix of elements related to "degree of harm" and "probability of occurrence of harm" and assigning a risk score to the cell where each element intersects.
risk graph method
A method to determine the branch path of evaluation for each risk element and finally derive the risk level

The four risk assessment techniques mentioned above are commonly used.There is no set rule as to which method to use, and the method that is easy for the risk assessor to use is selected and used.

4. Risk evaluation

As a result of estimating the risk, we will decide whether or not the size of the estimated risk is acceptable, and if it is acceptable, the risk assessment will be completed.
If the risk is unacceptable, we will continue to implement “risk reduction”.At this time, it is necessary to determine the "acceptable risk" based on the safety concept of the company conducting the risk assessment, because it cannot be evaluated unless the acceptable risk is decided.

5. Risk reduction

Take action to make the risk acceptable for the risk assessed as unacceptable.