OHS Canada Magazine

Regular, intelligent machine safety audits can help protect employees

October 31, 2022
By Tim Knowles
Health & Safety Actemium Audits Machine Guarding Risk Assessment

(auremar/Adobe Stock)

Workplace safety is a serious issue which commands utmost respect and attention to protect workers and equipment. Canadian workers compensation boards reported that 924 workers died due to work- related causes in 2020.

The Workers’ Compensation Board of Nova Scotia states there were 516 serious injuries in the manufacturing sector in Nova Scotia in 2020. In Nova Scotia alone, manufacturing represents nearly 11 per cent of all serious injuries in the province.

That said, employers must be diligent to ensure their employees have the required information, training, and supervision to perform their jobs safely. They also need to ensure safe and properly functioning machinery and equipment. Whereas the employees in the plant setting have a right to be informed of any known or foreseeable hazards in the facility and to be provided with the information, instructions, training, and supervision necessary to operate machinery and tools, all to protect their health and safety.

Safety is no joke, and it’s always better for companies to invest in strict, regular safety audits to ensure protected workplaces and the well-being of their staff.

When to perform a safety audit

We recommend that safety audits be performed internally on an ongoing basis. Machines and the way people use them are always changing, and we need to continuously ensure that these changes keep users and operators safe.


Audits will reveal deficiencies in existing safety protocols which can then be addressed before tragedy strikes.

At every manufacturing location, it is essential to set a schedule for inspecting each machine on a regular basis to ensure its safe for various teams to work with. Safety is also not static, and safety devices and procedures are constantly being improved and refined. It is important to keep abreast of developments to see if new devices, procedures, or technologies could improve the safety of existing systems.

Internal audits can be tricky since they will lack fresh perspective of systems and procedures. Sometimes bringing in personnel unfamiliar with a machine to assist in a risk assessment or hazards analysis can help capture safety risks that those familiar with a machine might gloss over or take for granted.

Ultimately, an internal audit will dictate the need for an external, professional safety audit. When a company internally determines that a machine could present a hazard to operators, or others, that is when an external expert should be introduced to the issue, and the process of remediation should begin.

How is risk determined?

Many aspects of a manufacturing process could potentially cause harm to someone, from the lowering plate of a massive machine press to something simple like a sharp edge on a workstation or machine tool.

Beyond government safety regulations, which must always be followed, it is important to determine the risk of a given hazard by assessing its severity, the potential for exposure, the frequency of exposure, and the duration of exposure.

A company can effectively assess a risk once they have identified a potential hazard. Is the hazard near workers, are workers constantly exposed to the hazard, and what is the severity or potential injury that the hazard poses?

Machine guarding is often associated with workplace safety and is one of the most common methods for protecting personnel from hazardous machines. Machine guarding is, put simply, physical barriers installed around a machine which prevent access to the hazards within.

This is especially common within industrial machinery, and when designed correctly protects users from any debris which may be ejected from a given machine during operation. For example, this would protect workers in a brewery if a glass bottle exploded in the filling machine.

Physical guarding is also an effective method for preventing contact with moving parts, pinch hazards, high temperature components and other hazards.

Not every machine in a manufacturing plant needs machine guarding installed, as the need for guarding is determined using a risk assessment, a prescribed process for ensuring that all the hazards of a machine are captured and addressed. This process can be repeated to determine the need for improved machine guarding, or a simplified process known as a hazards assessment can be performed, which can similarly dictate the need for upgrades.

How does a safety audit play out?

Industrial automation companies get involved when a machine is suspected to be hazardous or has been identified as hazardous during an internal audit. The initial task is to interview people who regularly use the equipment identifying the issues that they feel need to be addressed. The workers who use the machine frequently are most likely to be familiar with potential issues.

Next step is a thorough examination of the machine guarding, as that is where issues most frequently appear.  Checking the electrical and pneumatic controls is essential, as they are often out of date in terms of current safety standards. The most common hazards are ones that have been present for a long time.

Eventually, things that have “always been done that way” become ignored.

It is important to stay vigilant and avoid this pitfall in the process of making workplaces safer.

Sometimes, safety audits are performed before a machine has been purchased, and thus the goal is to ensure that the machine builder is meeting the customer’s needs, should they differ to the standard employed by the machine builder.

Assigning SIS levels during an audit

A common aspect of safety audits is the Safety Instrumentation System (SIS), which ensures when a machine operator may encounter hazardous energies in a machine, those energies are dissipated and do not return until the operator has left the area. In Canada, the different SIS levels are referred to as Performance Levels and range from A (least protective) to E (most protective). Most companies aim for PLD, or Performance Level D. Every industry uses the same levels, but different industries trend towards the upper or lower end of the spectrum depending on the amount of capital they dedicate to safety.

Often, the financial cost of a safe facility is higher than plant owners and operators expect. However, it is considerably cheaper to maintain a safe manufacturing plant is safe ahead of time, rather than incur the costs associated with the Ministry of Labour closing a facility due to an injury. The smart decision is to make safety a real priority. Set aside a budget each year for the improvement and maintenance of safety protocols at your facility while ensuring that employee feedback is not only listened to, but also acted upon.

When a risk assessment is carried out, the most important aspect is capturing all the risks of a machine or workplace. To this end, it is essential to include representatives from operations, maintenance, sanitation, management, and any relevant groups in safety discussions. Each group must understand the risks and hazards which might be present within the part of the machine they most often work with.

After all, safer machines allow for easier resource distribution since they require less training on the part of a prospective operator. If safety systems across an entire facility follow the same design philosophy, it also cuts down on training time.

Managing hazards and mitigating risk

It may sound obvious, but the best solution is one which eliminates the hazard present in a machine or workplace. This is also often the most challenging to implement. The hierarchy of risk reduction is the same regardless of injury, and is composed of the following:

  • Inherently Safe Design
    • Engineer out the part of the manufacturing process which is causing the hazard. For example, if operators may be exposed to hazards while loading raw materials into a machine, incorporate an automatic loading system which eliminates the potentially hazardous task.
  • Safeguarding and Complimentary Protective Measures
    • Integrate machine guarding and other protective devices to eliminate access to the hazard. For example, if operators may be exposed to a hazard while loading raw materials into a machine, install a light curtain to stop the machine when an operator is loading the raw materials.
  • Information for Use
    • Comprised of signage, training, and PPE. For example, if operators may be exposed to a hazard while loading raw materials into a machine, add a sign indicating the presence of the hazard which instructs operators on how to properly load raw materials.

Safety upgrade projects also present the opportunity to examine other aspects of a machine beyond the identified hazard. If a machine needs hard-wired controls installed, why not install a safety PLC, and thereby upgrade the controls system at the same time? Currently, communication protocols that can work from an ethernet network are incredibly popular. They enable full safety-rated communications without the need for additional dedicated architecture. Auxiliary upgrades such as these ensure the safety and robustness of the system into the future.

Future safety technology and procedures

Just before the COVID-19 pandemic began, there was a widespread industry shift towards IoT solutions. This is often referred to as Industry 4.0.

At present, it is limited to companies with higher safety budgets, but these technologies will trickle down to more affordable devices and systems as time goes on. For the safety sector, this means better visibility into the internal logic of controllers and devices, and thus greater control over their functions. For example, whereas before a scanner might only tell you whether something was inside its sensor’s ranger, now it will identify exactly where the object is. This is especially beneficial in robotic and self-guided vehicular applications.

The future of manufacturing safety will likely be systems that allow operators to perform tasks in one section of a machine, while other sections continue to function. This is already somewhat widespread, but it will likely become even more common as currently expensive devices such as servo motors and robots become more accessible.

The importance of safety

It is true that ensuring the safety of a workplace and its equipment will demand a greater investment of time and money, but it is always the right choice. Performing regular internal safety audits will pay off in the long run, ensuring your facility, equipment, and most importantly, your workers are kept safe and able to operate.

Tim Knowles is P. Eng., FSEng (TÜV Rhineland), is a Senior Safety Automation Specialist with Actemium Toronto



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