Not Suitable for Medical Use – Electrical Safety Testing Under Attack

By Greg Smith, NCE
Certified Product Safety Engineer

You’re on the operating table, the surgery is almost over. The procedure has gone well. The doctors and nurses are walking in liquid on the floor covered with antiseptic, your blood, and other fluids. As your doctor is making the final repairs, a nurse is at the computer typing in some data, then she turns to assist the doctor, steadying herself with one hand on the computer monitor. As she touches the doctor, the faulty PC sends it’s stray current through both of them and directly into your heart. They feel almost nothing, but you are especially vulnerable and in a few seconds, it’s too late, the damage has been done.

How could this happen? Let’s examine the situation more closely and try to determine what might have gone wrong. In this unfortunate scenario, a number of things happened because of what people and organizations did and did not do. A special interest group of foreign computer manufacturers brought great pressure to bear on OSHA and bullied them into accepting only a “Manufacturers declaration”, as evidence of product safety. (For those of you who don’t know, this is equivalent to the “CE” mark, which is sometimes based on falsified documents). A national healthcare organization worked hard to have leakage current requirements stripped from NFPA 99. An IT department put a regular computer in a patient area and the cord became pinched, causing the ground wire to contact a metal frame. It’s possible there were people on consensus document committees who allowed this happen for “political” or other unknown reasons. Some other people in healthcare safety knew what was going on, but were afraid to act against these organizations. So now, the Biomedical Engineers were not allowed to test the computer. The hospital administration and the IT department forced purchasing to order regular “consumer” type computers for the operating rooms. The doctors and nurses did not even think to consider they might not be safe to use in the OR environment. You checked into the hospital not worrying about electrical safety of the equipment. In this story, you are now a victim of negligence and careless tampering with safety requirements. Too late.

Maybe it’s not too late. Maybe we can influence people and organizations, maybe we can have an effect on the outcome. It will take perseverance and patience, and it will not be easy. Electricity is invisible, which makes attacks on electrical safety so prevalent. In the beginning of electricity, many buildings and houses burned, and many basic improvements were made to prevent fires. At that point in time, people were very much aware of the hazards of electricity. It was feared and respected. In the 21st Century, we have 3 decades of improved levels of safety and 3 decades of safety professionals who have helped to protect people from these hazards. These days, many people only think about electricity when the power goes out. Periodically, we need to re-educate the public and professions so that people in the workplace don’t become complacent.

Can computer and non-certified equipment in hospitals kill patients? Product Safety and Biomedical Engineering experts know the answer is “Yes”, so do designers and manufacturers of safety-certified medical equipment. Why would an organization like ASHE (American Society for Healthcare Engineering) attempt to potentially cripple US Safety Standards and pressure the Joint Commission to have this testing stopped? At the same time, when it comes to the subject of inspection of equipment for US certification and enforcement of existing laws, ASHE is silent. Why are ASHE and the Joint Commission not aggressively encouraging the proper testing and deployment of computer equipment in hospitals under existing regulations and safety standards?

The following is a quote from a letter written in February 2009 by ASHE to the Joint Commission: “This is a rather timely subject as ASHE is working hard to debunk a lot of legend behind leakage current and with it remove it from NFPA 99….Our proposal has passed the public comment stage and has been accepted by the technical committee. So we anticipate a significant reduction in requirements for the 2010 NFPA 99 and hope for elimination in the 2013 edition”. Clearly, this shows ASHE’s intention to reduce the current level of safety currently in place. It’s important to consider that ASHE likely has no electrical product safety professionals in their “working groups”.

The TJC (The Joint Commission, formerly The Joint Commission on Accreditation of Healthcare Organizations), has also never taken a firm position on certification and testing of medical equipment, instead, relying on each organization to police themselves and attempt to identify and maintain safety-certified equipment. A search of the TJC website (www.jointcommission.org) reveals that there are no references to safety of electrical equipment, UL Standards, certification of Listed equipment, or leakage current. Also, there is no mention of 29CFR 1910 Subpart S, which requires all equipment in the workplace to be Listed or Labeled by an NRTL (Nationally Recognized Testing Laboratory). The term “Listed equipment,” means that equipment is certified by a US NRTL, including the use of applicable Standards, in this case UL 60601.

What is Leakage Current and how does it directly affect the human body? Leakage current is the amount of electrical current which is always present in a piece of equipment or system. Leakage current tests remove the protective ground to see how much current would flow through a person when the ground is disconnected. If a piece of equipment is designed with improper grounding or compromised ground this will result in direct or indirect harm to high risk and other patients. Normal use of portable, cord-connected equipment can lead to the risk of leakage current due to wear and tear on cords and plugs. Also, if a connection plug is incorrectly re-attached, exposure to leakage current will result. These anticipated conditions and the resulting leakage current can cause cardiac arrest.

Studies on leakage current in humans show that leakage current will cause heart failure in certain patients, especially for high risk patients. However, everyone involved with patients or present in these areas are exposed. For example, if a healthcare worker touches a piece of equipment with higher than safe leakage current and also touches the patient, the patient and the healthcare worker will be put at risk. If a piece of equipment is worn or damaged, the likelihood of shock or energy hazard increases. (1)

Electrical Safety Standards are written due to deaths, and / or because of obvious, imminent, scientifically verifiable threats to human life and well being. This applies to many aspects of product safety, including grounding, dielectric voltage withstand, leakage current, short circuit, abnormal conditions, single fault / multiple fault temperature / overload, explosion, radiation and chemical hazards, incorrect use of components and more.

For medical equipment, the primary standard for many years was UL 544, Safety of Medical and Dental Equipment. (2) This standard also requires that power supplies be certified as protecting any low voltage circuits, and often requirements for medical grade cords, plugs and other components. UL 544 was a UL (Underwriters Laboratories) standard, a consensus product safety standard, and was created with cooperation from product safety engineers, design & manufacturing specialists, medical / biomedical and inspection authorities. Products that met this necessarily strict standard became the best performers in healthcare, and the US and international safety agencies. In the last edition of UL 544, leakage current for ground to chassis was 300 Microamperes, (300uA). Depending on the specific medical device, leakage current limits are as low as 10uA. For example, a non-patient connected device like a spirometer (connect to the patient by a plastic tube / air only) requires a maximum of 300uA leakage current from chassis to ground. An electrosurgical generator, for example, is in direct patient contact with applied voltage, so the limits are extremely low, in some cases as low as 10uA. (3).

UL 60601 is the US version of an internationally “Harmonized” Standard, from the original (International) IEC601. The US version contains national “deviations” to account for differing voltages and national requirements for the United States. The leakage current limits and electrical safety requirements are very similar to the UL 544 limits. The AAMI Standard, used by Biomedical Technicians is similar to IEC601, and requires a chassis to ground maximum of 500uA. (4). The advantage of the Harmonized Standards is the ability of testing laboratories to complete the final items for US certifications. Despite the differences, the requirements for leakage current are now similar worldwide. Another result of this harmonization is that X-Ray equipment, including portable X-Ray units, are now subject to the 60601 requirements. NFPA99 has similar testing requirements and leakage current limits. (5).

Why is certain equipment not suitable for Medical Use? Why does medical equipment undergo different / more rigorous evaluation and testing than other categories of equipment? Why would unsuitable equipment be moved into OR’s ICU’s and other patient exam areas?

For medical equipment, added safeguards and testing is required. There are many areas where such equipment (referred to as “medical grade”) needs to be used: Operating Rooms, Emergency, Intensive Care Unit, and all patient care and exam rooms. Listed medical equipment often has special markings, such as “Do not use in the presence of flammable anesthetics”, and “Grounding reliability can only be achieved with the use of a Hospital Grade receptacle”. When you see this kind of equipment and Hospital Grade receptacles in the facility, then you will know that other equipment in these areas must meet the requirements for medical use, such as computers, computer monitors, x-ray film viewers, etc. (6)

Many pieces of equipment do not belong in these areas, such as: microscopes or other laboratory equipment, regular “consumer” computers, office furnishings or lights not Listed for medical use, and many other products. (7) Still, there are many healthcare facilities that have no incoming inspection for equipment, or no one on staff that would recognize a “non-certified” piece of equipment. Many distributors do not even know the difference, while some do know and try to pass off “CE” marking as a certification mark. (“CE” is not a certification mark). Sometimes, physicians request very new or prototype equipment directly from a distributor or manufacturer, bypassing any incoming inspection by biomedical engineering or purchasing that might be in place. Much of this new equipment has never been tested for safety, and can put the physician and the healthcare provider in the unfortunate position of potentially harming the patients they are trying to help.

In addition to more rigorous requirements for electrical safety, NRTL certified devices have to meet requirements for Electromagnetic Interference and Compatibility (EMI / EMC). This means that these devices have to be designed and tested to receive interference from other devices without malfunctioning, and to function without interfering with other devices. Equipment not certified for medical use does not have to meet these requirements. Also, many devices not certified for medical use do not meet the requirements for enclosure construction, and can be easily damaged from fluids commonly used in healthcare facilities. This compromising of a device with fluid ingress can lead to short circuits and shock, electrocution.

There are many examples of Medical equipment suitable for use in patient areas. Cybernet makes a medical grade computer (www.cybernetman.com). Maxant Technologies manufactures medical display workstations (www.Maxant.com). Both of these companies have their products Listed to UL 60601. These manufacturers understand the requirements, and have testing lab certifications specifically for healthcare facilities.

In some situations, it is possible to use equipment not specifically built or certified for patient areas by using a medical grade isolation transformer. For example, Powervar makes a UL 60601 Listed isolation transformer (www.powervar.com). However, if an isolation transformer is used, it needs to be configured so that the equipment plugged into it cannot be easily unplugged and plugged into a wall receptacle. This can be accomplished by using a locking mechanism, a non-standard cord configuration, or by blocking access to the transformer with the use of a mechanically secured cover that requires a tool or key to open. or connected within a medical “Cart” if the assembly is also a certified system. The difficulty with this is that these “cart” systems are often made up of other certified or non-certified products that fail other medical product criterion. The best possible solution to these problems is a product specifically manufactured and certified to the medical Standards.

Brud Sturgis is the president of Maxant Technologies. Maxant designs and manufactures equipment especially for healthcare patient and OR Environments.

Q. t does it take for a manufacturer to excel in designing and building of medical devices?
A. We need to employ an educated and highly skilled and trained Electrical and Mechanical Engineering team. They need to understand and apply regulations such as UL 60601, as they relate to the Healthcare Environment. We design a custom product to meet regulations, we assemble manufacturing talent, procedures and assembly capability to build and deliver the product. This includes developing relationships among component manufactures and design teams. We also develop the capability for proper testing and verification of each product family and individual unit shipped, and we must be able to build and ship product within very specific price and budget restrictions. As a company, we have to understand the needs, wants and expectations of all providers and users within the healthcare delivery system.

Q. How does your experience and expertise differ from a computer manufacturer?
A. Unlike a computer manufacturer, we work closely with end-users to define use parameters and identify the proper product to meet specific needs. We have to understand the in-depth nature of the healthcare delivery systems and how one modality differs from another. Our quality and design characteristics needs to be of a higher standard in order to function in heavy use and lengthy periods of 24/7 use. We need to have the ability to communicate effectively with doctors and skilled IT professionals to identify needs and configure the features of each product built.

Q. Are there companies selling non-medical grade product into this market in competition with you?
A. Yes there are…..however most of the major computer manufacturers are issuing disclaimers in their product literature that their product does not and is not intended to meet medical use standards in patient care areas. These disclaimers and warnings are most often ignored when reaching IT and purchasing decisions. Regardless, non compliant equipment invariably finds its way into patient care areas thus putting patients at risk.

Q. How do you insure regulatory compliance?
A. We had to develop in-depth knowledge of all possible regulations and requirements, then design and build units which are capable of meeting or exceeding these regulations Every unit is tested prior to shipment to insure that all rules and regulations are met. For example, the Maxant Mediport is the only high performance all-in-one workstation designed and tested to meet 60601 and NFPA99 requirements.

Q. How does the added requirement of meeting rules and regulations (60601 and other) translate in costing and pricing decisions?
A. To insure the quagmire of higher standards required in hospital we work closely with Federally approved Nationally Recognized Testing Labs including UL and Met Labs. To meeting these requirements, there are considerable added component costs and manufacturing expenses incurred. For example, we are required to acquire and maintain sophisticated testing equipment and procedures to insure each product built meets all appropriate standards. Also, the quality and reliability of costly components must be insured to meet the demands of high use healthcare environments All these factors add considerable expense to Cost of Goods Sold while still having to meet severely limited end-user budget requirements.

Federal Law (OSHA) 29CFR1910 requires that all electrical equipment in the workplace be listed or labeled by a Nationally Recognized Testing Laboratory. Other states, jurisdictions and hospitals have additional requirements. Although these laws might not be well known by the general public, those in electrical safety are familiar with them, and understand the importance and life-saving qualities of these requirements.

Some will claim that it is OSHA’s responsibility to police safety in the workplace. Electrical safety groups such as ACES (American Council on Electrical Safety), have been working with OSHA to promote training of OSHA inspectors to enforce current laws, but it is an uphill battle for several reasons. Due to budget and personnel limitations, OSHA most often visits a workplace after someone has already died. The fact that OSHA does such a poor job of enforcement leaves the workplace owner with all the liability for injuries and deaths. When there are incidents of this nature, the workplace owner is then forced to bring lawsuits against equipment manufacturers and distributors, and anyone else responsible for bringing or allowing this equipment in the workplace. This can include inspectors, contractors, hospital safety committees, risk management directors and others.

FDA-problems and misconceptions. The FDA (US Food and Drug Administration) is the government agency concerned with many issues and areas, most having no bearing on safety of equipment. Although there are FDA requirements for medical equipment, these requirements are not generally related to electrical safety of this equipment, rather they focus on correct and reliable operation of equipment.

The FDA has an “incident reporting” database called MAUDE. While this database is interesting, it has no search parameters for electrical injury and death resulting from causes related to product safety. Additionally, this database is a voluntary reporting database for incidents, relying on a variety of different sources. Many of these sources are people who have no training in electrical safety, and are not even minimally qualified to judge the root cause of the incident, much less to determine if an incident was the result of leakage current. In the end, this database is not a reliable source for any scientific analysis of electrical injury or death from equipment.

The FDA also ignores the issue of electrical safety certification to US Standards. Many do not understand that because a device functions correctly does not mean it is electrically safe. Additionally, The Project on Government Oversight reports that decisions by senior FDA officials in 2006 eliminated critical measures that keep manufacturers of medical devices compliant with high quality standards. (8). Many other problems with the FDA make it a highly questionable source for research on the subject.

In a recent regulatory bulletin provided by Bureau Veritas, is was revealed that under the provisions of legislation introduced earlier this year in the U.S. House of Representatives, manufacturers may soon face liability for medical devices that harm consumers, even if those devices received pre-market approval from the U.S. Food and Drug Administration (FDA). The proposed Medical Device Safety Act of 2009 would amend the Federal Food, Drug and Cosmetic Act to provide legal recourse to patients who are injured by a medical device that malfunctions. Under a 2008 ruling by the U.S. Supreme Court (Reigal v. Medtronic), individuals who claim injury due to the use of a medical device may not sue the manufacturer if the device received pre-market approval from the FDA. According to Congressional Representatives, that ruling resulted in the dismissal of 1,400 separate lawsuits against device manufacturers. Recently, the House Energy and Commerce Subcommittee has concluded hearings on H.R. 1346 and in the Senate, the legislation has been referred to the Committee on Health, Education, Labor and Pensions. A summary of the text of S. 540 can be viewed at: http://www.govtrack.us/congress/bill.xpd?bill=s111-540 A summary of the text of H.R. 1346 can be viewed at: http://www.govtrack.us/congress/bill.xpd?bill=h111-1346. (9)

Why would the US Congress considering a bill that would allow lawsuits against FDA approved products? Most likely because FDA approved products have injured and killed, and the Supreme Court decision of 2008 was a grave mistake. As many of us in Product Safety are well aware, the FDA 510K “Pre-market approval” process is a flawed and highly questionable regulatory requirement. As more product recalls are being reported by the media, a new administration in Washington, D.C., and a newly appointed FDA commissioner who has said "there obviously have been some problems" at the Center for Devices and Radiological Health and has designated device reform as "a high priority" for the immediate future. Former FDA Commissioner David Kessler described the device center as "dysfunctional" and "in meltdown." According to the new FDA chief, Margaret Hamburg, “Agency scientists have said some devices that received 510(k) approval should have been required to show more data on safety and efficacy”. (10)

In addition to these problems, the FDA has historically ignored the requirements for electrical safety and Federal workplace law. Obviously the FDA in it’s current state is an unreliable source for any research or meaningful data.

Our Biomedical / Clinical Engineering departments are a major force protecting our patients and healthcare staff. These specially trained and hard working technicians and engineering professionals are working every day to insure the safety and proper operation of equipment for our procedures and operations. Their diligence and commitment to patient safety is generally unseen and under-appreciated, much like product safety certification experts.

Biomedical engineers and technicians perform preventive maintenance of portable equipment. These duties include repair and maintenance (cords, leads, equipment subject to abuse…), leakage current, grounding, and other tests depending on the equipment being used. They also ensure equipment is operating properly so that patients will not be put at risk from faulty equipment. Grounding is the weak link and doorway to leakage current injury. Regular tests are critical to ensuring these conditions do not put our healthcare workers and patients at risk. Frequency of tests required or recommended by product varies from 3 months to two years, depending on the type and use of the equipment. This is a well-known fact in the biomedical engineering field.

Additionally, many hospital Biomedical and purchasing departments inspect all incoming equipment for third party certifications and also to be sure the equipment is listed to the correct Standard. In many hospitals across the country, these departments regularly identify non-certified equipment. This non-safety certified equipment represents extreme hazards to everyone, especially when they have passed no initial tests during product certification, and have no limits for leakage current or any other safety tests. These Biomedical and purchasing departments are on the front lines of electrical safety in healthcare facilities. Recently, these departments have been reporting the use of regular consumer computer equipment in patient areas as being non-certified, but their objections have been ignored by hospital administrators.

Scott Trombley is a Certified Biomedical Equipment Technician (CBET) and has been working in this field for over 25 years. Previously with Cohr Masterplan, then with hospitals in Atlanta and now Central Florida. He is currently on the ( AHCA) Agency for Healthcare Administration’s "Expert list" and was a speaker at the 23rd AHCA seminar. Scott and his employer InterMed work closely with the biomedical advisory board of Santa Fe College. He is also a founding member of Tyler’s Hope, a non-profit organization in search of a cure for Dystonia - http://www.tylershope.org. Scott is currently VP of InterMed Biomedical Services where he oversees operations, employee safety and writes policy procedures to comply with authorities having jurisdiction. These AHJ’s include TJC, AHCA, city and county electrical Inspectors. Scott has the answers for questions about leakage current and other testing in healthcare facilities.

Q. Why are Leakage Current tests performed and how often are they performed?
A. We perform electrical safety inspections (ESI's) routinely as part of an Equipment Management Program. Whether it be on a scheduled device, loaner, rental, patient or physician owned, or post-repair, it is common that our technicians perform this test daily, along with other tests. Every day equipment fails these tests.

Q. What kind of test failures do Biomedical Technicians see, and what are the causes?
A. There are a variety of reasons for the excessive leakage current: Degradation of components, which over time one can demonstrate the relation of leakage to wear as the power supply or other components age or stress; damage abuse where a variety of neglect or accidents including missing or broken ground pins, spillage from fluids that egress and evaporate leaving excessive current leakage, defective power cords; instances where beds or other equipment may have damaged the conductors and cords. We see good systems connected by bad or inappropriate power strips, and we see inappropriate equipment for the patient care setting. All too often IT equipment intended for office or business finds its way into the clinical areas. These conditions can only be avoided by regular testing and inspection.

Q. Do hospital IT departments bring in equipment not suitable for patient areas?
A. Unfortunately it is a common practice for doctors, purchasing agents, equipment reps and IT departments try to bring ordinary computer equipment into healthcare facilities and patient areas. Sometimes it’s merely due to lack of knowledge of codes, standards Sometimes the equipment bought is certified but not certified for patient area use - there is a big difference between medical devices and all other equipment. Since some of this non-certified and inappropriate equipment makes it into these facilities, we get a chance to inspect this equipment. What are the differences? Only an expert with the right background and tools can answer that question. OSHA and many States realize this and this is why codes and laws are in place.

Q. What about non-certified equipment?
A. The situation is the same with non-certified equipment. Most Hospital administration departments and purchasing agents don’t know the inherent dangers associated with unknown and untested devices. The types of equipment vary from EEG devices to neuro-stimulation devices, computers, printers - the list is extensive. Many of these companies that know better and continue to sell uncertified equipment. I can tell you that most of the non-certified equipment I’ve seen required modification to be made safe. Grounding is a big problem in non-certified equipment, and grounding problems lead to leakage current exposure.

Q. What is the perception of product safety in the healthcare environment?
A. I live and work in Florida and in Florida State code requires NRTL certification to the appropriate intended use. When we point this out there are a variety of responses. The responses I receive vary from concern for patients and staff, to denial. Some worry about the legal aspects, others are genuinely concerned about the compliance to State codes, but many others see no problems and will address problems IF they occur. I hear a lot of comments such as , "Everybody else uses it" or, "We had one at the last hospital I worked at and our Biomed there never said anything". Of course, there are also many who will have any non-certified device inspected and tested and although this can be a challenge, it is a wise and prudent choice and the only way to really protect patients and healthcare staff.

Many deaths due to electrical shock and current have occurred since the widespread use of electricity. In the 1960’s, the issue of leakage current came to the forefront, resulting in the increased level of safety we now have in place. Many articles were written on the subject. (11). There are many ways electrical shock can occur in a healthcare facility, for example, humidity in the plugs of blood and fluid heaters causing device failure (12),Accidental toppling of a fluid container causing spillage onto a blood pressure monitor (13), Electric shocks to anaesthetists after touching a faulty device and the chassis of another device simultaneously (14), An anaesthetised patient was connected to an ECG device that had been wired wrongly with the earth and neutral connections transposed. (15)

How widespread are cases of death by exposure to Leakage Current? This information is difficult to obtain due to several factors: Patients simply die of “Heart Failure” with no further detail provided. Many of these patients are high-risk, and are exposed to electrical equipment in regions of the country where hospitals may not have biomedical engineering departments, and equipment. Many deaths go unreported, or are incorrectly reported, but may actually be caused by Leakage Current.

Correct equipment vs. cost. Computers are everywhere, and the number needed in a healthcare facility can make a computer equipment budget difficult. In recent years, the “cost first” approach has been driven by many departments and their budget managers. Computers and monitors made specifically for medical are more expensive. Why more expensive? What makes something a correct piece of equipment for a healthcare facility, especially patient areas?

The risk level and complexity of medical equipment requires expert design. This mean the designers need to be better educated and higher paid employees. If a company does not have these employees on staff, this cost is reflected in the needed time from special contract employees or consultants.

Equipment suitable for medical use also requires a manufacturer to buy specific correct specialized components, such as low-voltage protected power supplies, better insulated wiring, special enclosures and control electronics. This means that the manufacturing process will be more expensive, including the cost for regulatory inspections, production line testing and factory audits.

All these factors affect the price of this class of equipment, especially designed to treat injury, help improve quality of life and extend many lives.

US Safety NRTL system and the “CE” and “SDoC” threats. A US Nationally Recognized Testing Laboratory is a third party agency that ensures the highest level of safety and security needed for electrical products. Conversely, “SDoC” and “CE” are not Product Safety programs. A current issue of serious consequence for healthcare facilities (and also consumers) is the repeated attempts by special interest domestic and foreign computer manufacturing groups to gain acceptance of SDOC. This special interest group is again pressuring OSHA to allow these products to be sold on the market as equivalent of a US (UL or equivalent) Listed product. SDoC stands for “Suppliers Declaration of Conformity”. This is a “Self Declaration” program, similar to the “CE” sticker self declaration. This means that a company from anywhere in the world can simply declare their product meets the international electrical safety standards. In the testing laboratory business, we see these “self declared” products come in for evaluation and certification for North America on a regular basis. Some of these products are so far away from being compliant they represent an immediate hazard, especially for fire and electric shock. Recently, the EU has considered an additional product safety mark because of faulty, counterfeit and misrepresented products coming in from Asia. For the US, this SDoC program would mean that these cheaply-made, non-tested products like computers will end up in our homes and in our healthcare facilities. (16). Fortunately, we still have the OSHA Federal law for the workplace, 29CFR1910.303 and related sections which requires all electrical equipment in the workplace to be certified by a Nationally Recognized Testing Laboratory. (17). In addition to reputable and knowledgeable manufacturers, biomedical departments and firms, our NRTL engineers and inspectors are daily maintaining and improving the levels of safety with their work in the testing laboratory, and in the workplace with onsite testing and labeling.

Robert Stickels has worked in electrical product safety for 20 years, including as a regulatory design engineer for NCR. He is currently the Director of Field Evaluations for TUV Rheinland, and has personally inspected a great deal of medical equipment at numerous healthcare facilities. Robert is an Inspector Member of the IAEI, and on the Central Florida Division and State Chapter Board of Directors.
Q. When you are inspecting a non-certified piece of medical equipment, do you find test failures for leakage current? what kind of failures are you seeing?
A. Yes, I find test failures during leakage measurements. The equipment's components may or may not be certified. Many times I find components are certified and when combined into the end use product, the product as a whole does not meet the Leakage current requirement set fourth in the Medical standard. I see many failures between a few uA (Microampere) to 4 mA. (Milliampere).

Q. What kind of equipment have you found these failures in? Patient area? OR? Emergency?
A. This equipment is found in all areas. Case in point, Heart Cathlab A/V integrated system failed leakage current tests. The problem was with power supplies. The power supplies were not rated for use with medical equipment, instead they were Certified/Listed to the ITE standard. Due to the current requirement of the monitor a replacement power supply was not available. To fix the problem a medical grade isolation transformer was used to reduce the leakage current to acceptable levels. Other systems of concern are Patient beds, light fixtures and type of new procedure equipment, and others.

Q. What do the manufactures of this equipment say about these test failures?
A. Sometimes not much or nothing, often the manufacturer simply states; ”We have never run into this before" or "The equipment meets the NRTL requirements for the intended use”. System integrators use what is cost effective and meets the immediate need. Unless designed for medical area use, A/V equipment for use in a medical area typically may not available. Therefore testing and evaluation is necessary by an NRTL.

Q. What do the owners of the equipment say about the failures? Did they know they were buying non-certified equipment?
A. It's buyer beware. Typically the hospital and doctors do not have a clue, they only know what the equipment does as far as the procedure it’s intended for. The equipment is tagged for evaluation only when compliance is required by a local AHJ, Joint Commission, State Agency or an internal Hospital equipment acceptance procedure. Keep in mind that non- compliant equipment may range from as small as a relocatable power tap to OR equipment or to as large a DI water chiller system used for Dialysis patients.

This fact remains: Equipment that is not suitable for medical use can put patients and healthcare providers at risk for electric shock and death. In the Product Safety Consensus Standards writing process, there are two considerations for writing specific sections and values for exposure to electrical current and voltage. The first is a list with names of people who have died because of this hazard. The second is the scientific proof that without a particular requirement there would be an additional list of people who have died. Both of these areas can sometimes be difficult to quantify and substantiate. However, to suggest that critical testing, such as leakage current, should be stopped is like arguing that since cars have airbags we can save money by removing seat belts.

The writers of NFPA 99 understood the value of periodic testing of leakage current, especially for portable equipment, which is subject to particular abuses and wear. The leakage current requirements in NFPA 99 are similar to our UL 60601 product standard. This is why the ASHE position on Leakage Current testing is especially troubling and dangerous. In their proposal to cut sections of NFPA 99, they state that these requirements are being cut in order to “…manage risks while bringing efficiencies to the regulatory compliance burden faced by healthcare providers.” In other words, this is being done simply to cut costs. Any “re-engineering” of NFPA 99 should absolutely consider the existing US Product Safety Standards, (e.g.UL60601) and their scientific basis.

When an electrical product or system loses it’s ground, patients and staff are immediately exposed to leakage current. As research has shown, AC leakage current can cause complete cardiac arrest at low levels. Portable Listed medical products employ heavy duty cords and plugs to help avoid the loss of ground, however this condition is inevitable, especially when a piece of equipment is kept in service for many years. No one questions the physicist coming in to check the viability and correct operation of equipment that uses radiation. Conversely, since our track record with electrical incident and deaths has improved because of the correct application of US Standards such as UL60601 and NFPA 99, electricity has indeed become “invisible” and because of this success the practices of electrical safety are questioned.

With counterfeit products from Asia and special interests pushing things like the SDoC program, now is the time for increased vigilance, not for softening or the elimination of time-tested safety standards and product testing. The ASHE attempt to influence JCHAO and dilute NFPA99 should be closely scrutinized and their vested interest and motivations identified and monitored.

The laws of physics cannot be changed to suit a particular purpose. Lives saved by accomplishments of product safety and hospital biomedical professionals are in the thousands, possibly millions by now. The science behind prevention of death from electricity has guided the requirements of national and International safety standards. The history of electrical safety for medical equipment is the history of US industry, engineering, government and testing laboratory professionals developing consensus safety standards. These requirements cannot be sacrificed to suit the plans of any special interest group. It’s a formula for disaster: Politics + Electricity = Death. Where electrical safety is concerned it’s better to abandon politics and just do the right thing. In the case of medical equipment and electrical safety testing, we need to be allowed and encouraged to keep doing the right thing to protect our families, friends and communities.


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8. The FDA’s Deadly Gamble with the Safety of Medical Devices. Project on Government Oversight February 19, 2009.
9. 111th Congress of the United States, S-540: Medical Device Safety Act of 2009; (HR 1346).
10. Mundy, Alicia: “FDA Chief Eyes Device Group” The Wall Street Journal, June 17th, 2009
11. Bruner JMR MD: Hazards of Electrical Apparatus, Anesthesiology Mar.-Apr. 1967
12. Linko K: Testing a new in-line blood warmer, Anesthesiology 52:445-456, 1980
13. Accidental toppling of a fluid container causing spillage onto a blood pressure monitor (Singleton RJ, Ludbrook GL, Webb RK, Fox MA. Anaesth Intensive Care 1993.
14. Electric shocks to anaesthetists after touching a faulty device and the chassis of another device simultaneously (Singleton RJ, Ludbrook GL, Webb RK, Fox MA. Anaesth Intensive Care 1993.
15. An anaesthetised patient was connected to an ECG device that had been wired wrongly with the earth and neutral connections transposed. (Atkin DH, Orkin LR. Anaesthesiology 1973.
16. US Federal Register (at www.osha.gov). For more information on SDoC, go to www.osha.gov and type SDoC into the search box.
17. US Federal Register, 29CFR1910.303a, and 29CFR1910.399, Subpart S.

Greg Smith is a Nationally Certified Product Safety Engineer (INARTE) NCE. He is also an Inspector member of the International Association of Electrical Inspectors, and a professional member of other electrical safety organizations. Greg has personally inspected and tested thousands of devices for MET Laboratories (NRTL), and has visited hundreds of healthcare facilities in the course of electrical safety evaluations.

Greg Smith can be contacted by e-mail: gregs@fieldlabeling.com, and by phone at 919-524-4555.