How to Conduct an Effective Machine Safety Risk Assessment
Imagine that in your manufacturing facility, a $30,000 machine with unforeseen safety hazards has caused injury to your personnel. To mitigate the safety risk, you plan to install safeguards with an estimated cost of $20,000. What if you had instead identified these safety hazards during the machine’s design phase?
In order to design machines that are safe to operate and easier to keep within budget, the machine safety lifecycle helps manufacturing facilities identify safety hazards and mitigate risk to build safer machines before their installation and startup.
A machine safety risk assessment (SRA) is the first step in the machine safety lifecycle. Continue reading to learn what makes a safety risk assessment successful and how it makes your facility safer without going over budget.
What is a Safety Risk Assessment?
An SRA is a tool used to evaluate all hazards on a machine, specifically those that people will physically encounter. When building an SRA, the first step is to generate an extensive list of every possible task someone is required to complete on a machine. These tasks could include sanitation, maintenance, and more. The next step is to create a hazard list. Hazards can include noise, vibration, carcinogenic materials, radiation, etc.
With both a task and hazard list, you can begin the risk assessment by reviewing the combination of tasks and hazards and assessing them using specific methodology from industry standards. For example, if you have a task during which an operator loads a part into a machine, there may be a pinching or crushing hazard associated with it. Each one of these tasks needs to be evaluated for the entire lifecycle of the machine.
These combinations of tasks and hazards are used to generate a risk level that ranks different combinations based on their level of severity and likelihood of occurrence. Safety professionals use this information to identify the appropriate risk mitigation strategy.
What to do with a Risk Assessment
With an SRA, you can mitigate the risks that were identified at your facility. Engineering controls — designing out the risk or using safeguards — isolate personnel from the hazard. An example of this would be adding an airbag to a car. Administrative controls such as signage, Personal Protective Equipment (PPE) requirements, and training requirements can also change the way your personnel perform. These mitigations follow the hierarchy of controls which aims to protect workers. It outlines methods ranked from most effective to least effective, with engineering controls as the first opportunity of control.
It is also important to create safety requirements specification (SRS) documents that inform the designers how to incorporate safety into the machine. Once the design is complete, it can go through a verification process to see if it meets the requirements laid out in the initial risk assessment. If met, the design can then be built. This helps introduce functional safety into your facility.
Four Key Components to a Good Machine Safety Risk Assessment
To do a thorough and effective safety risk assessment, four key pieces should be considered.
The Right Team
A safety risk assessment needs to incorporate every task that can involve a single piece of machinery, which includes operations, maintenance, and sanitation. This process should involve a representative from each of these disciplines. If you only involve an engineer, they won’t have critical insight into how the machine is cleaned. If the machine must be taken apart, is that engineer aware of potential risks that could occur?
A small, informed, and diverse team is necessary to be able to recognize and understand all possible hazards.
The Right Time
To be accurate and comprehensive, safety risk assessments take time. Depending on the size of the system and complexity of the machine, a safety risk assessment can take from a few hours to a few months to complete.
The Right Information
Documentation is critical to a good machine safety risk assessment. Having the right documentation and schematics for a risk assessment will drastically help with the time commitment and accuracy.
The Right Facilitators
It is important to involve unbiased, certified facilitators for your risk assessment. TÜV Rheinland is a globally-recognized organization that provides certified functional safety engineers who have knowledge of major safety standards and best practices.
A good facilitator will know the major standards that guide a risk assessment. The international norm is ISO 12100 which provides the general principles for design and how to perform risk reduction. ISO EN 13849, which refers to machinery safety rather than process safety, gives the methodology on how to assess the required performance level of the safety system. The North American standard, ANSI B11.0, adds clarity to the two international standards including the hazard control hierarchy.
Considerations for a Risk Assessment
For an effective safety risk assessment, there are several factors to take into consideration.
- Avoid an isolated safety risk assessment where only one person or specific group of people are conducting the assessment.
- “Why in the world would anyone do _____?” If you can think of it, someone might try it. Consider all possibilities no matter how improbable.
- Avoid underestimating or overestimating (therefore overestimating complexity and cost) the severity of a hazard.
- Avoid overcomplicating something that should be simple.
- Avoid settling for one solution as the only solution.
Working Towards a Safer Facility
Properly implemented functional safety will lead not only to safer personnel, but also to productivity gains with less hazards and risks for misuse of a machine.
Safety risk assessments are not always black and white, which is why having a certified safety professional to help you on your safety journey can make a huge difference. Our TÜV Rheinland certified Team can help your facility reach your safety goals. Contact us today.
