top of page
ISO 12100 - Risk Assessment Guide
In this guide, SAI will clarify the ISO 12100 standard and how it can be used to help you, as a machine manufacturer, create your own risk assessment and fulfill one of the key requirements to your Technical Construction File.
Key Terminology
Limits: the boundaries of a machine's intended use, encompassing both the normal operating conditions and reasonably foreseeable misuse, taking into account all phases of the machine's life cycle, including transport, assembly, operation, maintenance, and dismantling
Risk: a combination of the probability of occurrence of harm and the severity of that harm
Hazard: a potential source of harm, meaning a situation or hazard that has the potential to cause injury
What is it?
ISO 12100 is a Type A standard that demonstrates the general principles needed to create your own risk assessment for your machine. It defines the basic terminology, general procedures and principles, and documentation required.
Step 1: Determine your Limits
The first step that you will want to complete is identify your machine's limits. Creating this list will help you frame your risk assessment as you identify hazards associated with those limits. In ISO 12100, Clause 5.3 shows many different examples for limits to help you select the best ones that fit your machine. These limits are split up into "use limits", "space limits", "time limits", and others. See below for more information on these examples provided in the standard.
By understanding the actual machine limits of your machine, you can construct the hazard list around those limits based on how the machine will be used, the space it will occupy, the time it will be in service, and a few other factors.
Step 2: Identify your Hazards
Once your limits have been identified, the hazards related to those limits can now be identified. When identifying all hazards, the manufacturer must do so in a systematic way to ensure a thorough list. The entire life cycle of the machine must be taken into account. Using the following categories as reference is a good start to help you systematically identify your hazards:
-
Human interaction during the whole life cycle
-
Unintended behavior of the operator or misuse of the machine
-
Task identification: Setting, teaching, programming, operation, cleaning, and maintenance
Also, ISO 12100 provides helpful examples that can be used to identify your own machine's hazards. By reviewing the hazard examples, the hazards existing in the machine can be more easily identified.
For mechanical hazards, essentially any potential injury caused by moving parts of the machine must be considered. For non-mechanical, these hazards can include electrical, noise, vibration, and other types of stored energy that have the potential for injury.
Step 3: Estimate your Risk
After the hazards have been identified, they will need to have a Risk Priority Number (RPN) calculated for each of them. ISO 12100 states: Risk is a function of the Severity of the harm that can result and the Probability of Occurrence. By referencing the tables below, the risks can be assigned a number so that the overall RPN for each risk can be calculated.
Step 4: Mitigate your Risk
The final step in the risk assessment process is to mitigate your risks. Risks only need to be mitigated if they continue to pose hazards. If the RPN calculated above is above a certain value, use the following steps to mitigate the risk:
-
Re-design the machine to remove the risk
-
Use safeguards and safety functions to reduce the occurrence of the risk
-
Implement trainings to reduce the occurrence of the risk
When introducing safeguards and safety functions, it must be ensured that the safety function implemented meets the requirements for which is dictated by the overall risk it is mitigating. If you need further help on developing your safety functions and ensuring they are designed to meet your risk level, check out our Functional Safety Resources.
bottom of page