Electrical Safety Testing for Medical Equipment

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What is electrical safety testing for medical equipment?

Not all “test and tag” services are created equal. Electrical safety testing for medical equipment includes testing that addresses specific risks associated with medical devices. These risks are directly related to the transfer of electrical energy directly through the equipment’s applied parts, or indirectly through the frame and body of the device. Failures of the electrical system can lead to electricity related harms including shock, burns, electrocution and electrical cardiac injuries.

Electrical safety testing is the means by which these risks are mitigated. It includes measuring the insulation resistance, earth ground resistance, touch current, and other variables of the medical electrical system. AS/NZS 3551 is the standard that, among others, covers medical electrical safety testing. You must comply with this standard if you operate medical electrical equipment in Australia and New Zealand. The standard emphasizes creating a management program to ensure your medical electrical equipment works safely throughout its lifetime – from the day its commissioned until it’s retired. The principles and requirements in this standard are based on internationally recognised electrical safety standards, like IEC 60601.

Why perform electrical safety testing?

There are many benefits to performing electrical safety testing. It’s an essential way to demonstrate compliance with all applicable regulations. These regulations exist to promote the health and safety of the public. By regularly performing electrical safety testing, you can discover faults and failures before they cause issues. We will work with you to correct any findings and explain what factors may have led to the issues arising. During this process, you and your organization will benefit from learning about how to prevent problems during your day-to-day activities. For example, you can learn things like how to prevent damage to flexible power cords that could cause them to fail testing.

You’ll optimize the benefit to your operation by taking a comprehensive approach to risk management. Electrical safety testing reduces risk of harm to your staff and patients. Another benefit of this service is the offset of liability – maintaining your facility’s electrical system and keeping records of the testing, performance verification, and maintenance you perform is a great way to demonstrate you have done your due diligence.

Who needs to perform electrical safety testing?

If you’re unsure if you need to perform electrical safety testing, check to see if your facility falls into one of the categories on this list, or contact us to learn more. It’s good practice to perform electrical safety testing regardless of the industry you operate in. Consider the risk people face when operating tools like you’d find in a metal shop: drills, welders, and torches all have the potential for causing harm to the people that operate them. They could be burned or electrocuted if the equipment they operate is not properly maintained.

It’s very similar for medical practices, but instead of operating their equipment on raw metals, the people who work in these environments are working on other people! The risk is much more complex for medical practices because you must consider the operator of the medical equipment and the patient receiving treatment. Medical practices that operate equipment that produces ionizing radiation (such as x-rays), lasers, or other energy-based devices need to ensure these devices are safe to use. For medical practices, electrical safety testing following AS/NZS 3551 provides that reassurance. Any facility with a Patient Treatment Area will need to have electrical safety testing performed.

Electrical Safety Testing (AS/NZS 3551) VS. Management programs for medical equipment (AS/NZS 3760) — what’s the difference?

In general, AS/NZS 3760 applies to all businesses that own and operate electrical equipment. However, medical equipment is an exception to this standard. AS/NZS 3551 was created specifically to address safety concerns that only arise from devices that are used for medical purposes. The difference is the application: you can think of AS/NZS 3760 as the standard for any electrical equipment that’s used on materials, whereas AS/NZS 3551 is the standard for devices that are used on patients.

AS/NZS 3760 overview

AS/NZS 3760 is the standard that covers in-service safety inspection and testing of electrical equipment. As the name suggests, this is a comprehensive standard for electrical equipment that covers safety inspection and testing for the lifetime of the electrical equipment. It’s a standard that applies to a wide variety of general service business, like:

  • Schools and Government
  • Workshops and Factories
  • Hotels
  • Restaurants
  • Engineering and Construction companies

In terms of the requirements, this standard has a lot in common with AS/NZS 3551. Inspections cover visual examination of the equipment and supply mains, testing includes insulation resistance and leakage current testing, Businesses following this standard are required to keep records of all tests and inspection, including a register of repairs and corrective actions, for a retention period of at least 7 years. A competent person is required to perform the inspection and testing or “test and tag” service, which means someone with the appropriate training and qualification.

However, AS/NZS 3760 states directly in the scope that the standard does not apply to medical electrical equipment, and instead points to AS/NZS 3551. Therefore, “test and tag” service following this standard is a waste of time and money for medical practices’ medical equipment, typically found in their patient treatment areas.

AS/NZS 3551 overview

Medical equipment management activities have similar but even more stringent record requirements compared to AS/NZS 3760. Protective earthing resistance is one element of testing that’s different between AS/NZS 3551 and AS/NZS 3760. For medical electrical equipment, the limit is only 200 mΩ, whereas for general electrical equipment resistance up to 1 Ω is acceptable. That may not seem like much, but for highly sensitive electrosurgical equipment it can be the difference between life and death! Testing following AS/NZS 3551 usually consists of:

  • Visual inspection of external mains supply components,
  • Protective earthing resistance testing,
  • Insulation resistance testing,
  • Touch Current testing,
  • Earth leakage current testing,
  • Patient leakage current testing, and
  • Mains contact current testing.

Electrical safety testing in this standard covers all aspects of the equipment that are connected to a power source or could potentially be energized by a power source. Touch current is measured in normal conditions with the medical equipment in the patient environment to ensure that the current is less than 100 µA. The insulation resistance is also measured for the mains connection and the equipment enclosure. The requirements for these tests are high resistance (1 MΩ or greater) to ensure that any excess energy would be redirected to the connected earth ground, and not through the body of the device.

Socket-outlets include an earth ground connection, which normally helps to dissipate any excess energy from the device. Electrical safety testing also checks the equipment in an earth open state – this is done to ensure that if there were any problem with the earth ground connection, the equipment would still produce a touch current of less than 500 µA. Additionally, earth leakage current is measured for multiple socket-outlet systems to ensure earth leakage current never exceeds 5 mA.

As part of complying with this standard, your organization must also maintain a medical equipment database. This database contains a record for each item or system in your practice, which describes the date it was implemented or installed, testing dates, servicing and repairs, and the entities performing periodic testing and servicing. Even further, if a device is configurable for multiple applications, the database includes a record of the configuration the device is intended to be used for. Records must indicate who is contracted for medical equipment management activities, who has the responsibility for maintenance of these records, and any organizations you’ve subcontracted for testing and other services.

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How often should medical equipment be tested?

Electrical safety testing must be performed at least every 12 months, unless your organization has robustly documented justification for less frequent testing as part of an established risk management process. Additionally, anytime there are modifications or repairs to an existing medical electrical system, you’ll need to do performance verification before placing that equipment back into service. Equipment testing requirements vary from one manufacturer to the next. The frequency of testing and inspection are all based on the risk associated with the device. You should consult your instructions for use from the manufacturer if you’re unsure.

Why don’t practices get it done?

Often when a medical facility fails to perform electrical safety testing, it’s because they just don’t know it’s required and regulated by the Therapeutic Goods Administration. Management in any size organization is still held accountable though, so it’s important to understand the process and show evidence of oversight at the very least.

Generally, medical practices that fail to perform routine testing end up in this situation because there is no party responsible for these activities. This is especially true for small businesses, where a few people must perform many different roles. If you are responsible for asset management, then you’re likely going to also be responsible for ensuring that electrical safety testing is performed on a regular basis.

No matter what your situation, we’re here to help. You can Contact Us to schedule your electrical safety testing!

What happens if you fail to have your medical equipment tested and verified?

The longer you wait, the more likely you are to encounter a problem. It is impossible to predict the magnitude of such an occurrence, so if you’re operating at risk, you should always consider the worst-case scenario. For medical devices, the risk of injury or death caused by electrical system failure is significant. You expose your organization to increased liability the longer you wait to have your systems inspected, tested, and serviced.

Anytime an injury or death occurs as a result of the failure of a medical device, the issue is thoroughly investigated by the manufacturer and reported to the authorities. Patients may also report adverse events on their own. Even if the organization where the event occurred does not report the incident, they may be investigated. The equipment may be quarantined for examination and those involved may be interviewed.

Another consideration is that using diagnostic medical equipment without proper maintenance and testing may lead to misdiagnosis. You could be accused of Medical negligence – especially if you attempt to diagnose a patient with a device that has not been properly maintained. For certain kinds of medical electrical equipment, like electrocardiograms or ECG for example, problems with the power supply may result in a noisy output, missed signs, or prescribing unnecessary treatment.

What to expect with your Electrical Safety Testing service when you use Biomedics:

  1. When you submit a request through our Contact page, email us, or call us at 0407 999 937 one of our team members will respond the next business day.
  2. We will work with you to schedule a date for the service that has the lowest possible impact on your practice.
  3. We ask that you allocate one exam room or other space to be available for the day to accommodate our testing equipment. We’ll use this space for testing as much as possible and bring equipment in and out as needed to minimize any distraction to your staff and patients.
  4. Each device will be subjected to Performance Verification that encompasses physical, functional, and electrical testing. This gives you hard evidence that all your medical equipment functions as it should within manufacturer’s specifications.
  5. We will then perform the Electrical Safety Testing to check the medical electrical system, and all non-medical electrical equipment used in the patient environment.
  6. At the end of the process, you’ll receive a full report for accreditation with a label(s) attached for performance verified and test completion dates.