Commercial Grade Computers are Not Suitable for Medical Use

by Greg Smith, NCE
Can computer equipment in hospitals kill patients?
June 2009

Dear Healthcare Professional:

"Commercial Grade Computers are Not Suitable for Medical Use"

Can computer equipment in hospitals kill patients?

The following whitepaper is written by a Certified Product Safety Engineer who is involved in electrical safety inspection in healthcare facilities across the country. It describes the current state of regulatory affairs and proper testing procedures for electrical product safety within healthcare facilities.

Please review and distribute this whitepaper to all appropriate parties that are involved in the decision making process of purchasing electrically-powered equipment for all patient care areas within your facility. This might include, but not be limited to, Purchasing Managers, IT Managers, Department Managers, Bio-Med Engineers, Risk/Safety Managers, Hospital Administrators, etc.
Anyone in your facility that is concerned about patient safety and the risk of liability for patient harm should be made aware of proper testing procedures and the standards involved for these types of products.

We are concerned about the current state of regulatory affairs and how they are evolving as they pertain to electrical equipment within healthcare facilities. Our wall-mounted MediPort Digital Imaging Workstations are fully tested and certified to all of the electrical "medical" safety standards named in the article. Please keep patient safety a number one priority when purchasing new electrical equipment for your facility. If you have any questions on the content of this whitepaper or on our MediPort workstations, please call us at 800-307-4190 (847-588-2280 local) or visit our website www.maxant.com.




Commercial Grade Computers are "Not Suitable for Medical Use"
April 2009
Computer Equipment in Healthcare Facilities

By Greg Smith, NCE
Certified Product Safety Engineer

Can computer equipment in hospitals kill patients? Product Safety and Biomedical Engineering experts, as well as designers and manufacturers of Safety-certified medical equipment, know the answer is "Yes".
Why would an organization like ASHE (American Society for Healthcare Engineering) attempt to potentially cripple U.S. 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 U.S. 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 has no product safety professionals in their "working groups".

The JCAHO (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 safety-certified equipment. A search of the JCAHO 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 U.S. 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? If a piece of equipment is designed with improper grounding or a compromised ground this can result in direct or indirect leakage current shock from the device and potential 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 heart failure.

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/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 also states 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 and manufacturing specialists, medical/biomedical and inspection authorities. Products that met this necessarily strict standard became the best performers in healthcare, and the U.S. 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 (connected 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 U.S. version of an internationally "Harmonized" Standard, from the original (International) IEC601. The U.S. 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 advantage of the Harmonized Standards is the ability of testing laboratories to complete the final items for U.S. certifications. Despite the differences, the requirements for leakage current are now the same 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 (4).

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 Units, 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. (5).

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 (6). 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 a "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.

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.

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.


FDA problems and misconceptions. The FDA (U.S. 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 U.S. 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 (7). Many other problems with the FDA make it a highly questionable source for research on the subject.

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.

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 (8). 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 (9), accidental toppling of a fluid container causing spillage onto a blood pressure monitor (10), electric shocks to anaesthetists after touching a faulty device and the chassis of another device simultaneously (11), or an anaesthetised patient connected to an ECG device that had been wired incorrectly with the earth and neutral connections transposed (12).

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 do not have biomedical engineering departments and testing 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 means 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, 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, they are specially designed to prevent injury, help improve quality of life and extend many lives.

U.S. Safety NRTL System and the "CE" and "SDoC" Threats. A U.S. Nationally Recognized Testing Laboratory (NRTL) 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 U.S. (UL or equivalent) Listed product. SDoC stands for "Suppliers Declaration of Conformity." This is a "Self Declaration" program, similar to the "CE" sticker. 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 U.S., 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 (13).

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 issues are currently difficult to quantify and substantiate. 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 to cut costs. Any "re-engineering" of NFPA 99 should absolutely consider the existing U.S. Product Safety Standards, (e.g. UL60601) and their scientific basis.

When an electrical product or system loses its ground, patients and staff are immediately exposed to leakage current. As research has shown, AC leakage current even at low levels can cause complete heart failure. 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 U.S. 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 JCAHO and dilute NFPA99 should be closely scrutinized and their vested interests 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 U.S. 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.


Bibliography

1. Swerdlow CD, Olson WH, O'Connor ME, Gallik DM, Malkin RA, Laks M: Cardiovascular Collapse Caused by Electrocardiographically Silent 60-Hz. Intracardiac Leakage Current: Implications for Electrical Safety. Journal of the American Heart Association, 1999; 99; 2559-2564.
2. Underwriters Laboratories (UL). Medical and Dental Equipment, 4th ed. Northbrook (IL): UL; 1998. UL 544.
3. Eisner L, Brown RM, Modi D: Leakage Current Standards Simplified, Medical Device & Diagnostic Industry Regulatory Outlook, 2004.
4. UL 60601-1, "Medical Electrical Equipment, Part 1: General Requirements for Safety" (Northbrook, IL: Underwriters Laboratories, 2003).
5. Underwriters Laboratories (UL). Safety of information technology equipment, including electrical business equipment. 2nd ed. Northbrook (IL): UL; 1993. UL 1950.
6. American National Standards Institute. American national standard for leakage current for appliances. Northbrook (IL): Underwriters Laboratories; 1992. ANSI C101-1992.
7. The FDA's Deadly Gamble with the Safety of Medical Devices. Project on Government Oversight February 19, 2009.
8. Bruner JMR MD: Hazards of Electrical Apparatus, Anesthesiology Mar.-Apr. 1967
9. Linko K: Testing a new in-line blood warmer, Anesthesiology 52:445-456, 1980
10. 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.
11. Electric shocks to anaesthetists after touching a faulty device and the chassis of another device simultaneously (Singleton RJ, Ludbrook GL, Webb RK, and Fox MA. Anaesth Intensive Care 1993.
12. 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.
13. U.S. Federal Register (at www.osha.gov). For more information on SDoC, go to www.osha.gov and type SDoC into the search box.

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.