A Review of ESDA’s TR29 “Guidance for Control of Electrostatic Hazards in Healthcare Facilities”

Electrostatic discharge (ESD) poses significant hazards in healthcare settings, affecting both patient safety and the functionality of medical equipment. Understanding these hazards is crucial for implementing effective prevention measures.

The earliest concerns with ESD in the healthcare environment were related to preventing ignitions of anesthesia caused by ESD. In 1953, the Bureau of Mines published “Static Electricity in Hospital Operating Suites: Direct and Related Hazards and Pertinent Remedies”¹. This document provided technical background on the nature of these hazards and prescribed the use of static control flooring and equipment grounding to mitigate this risk. Since that time, the National Fire Protection Agency (NFPA) created NFPA 99 “Healthcare Facilities Code”² to help prevent fires and explosions in healthcare facilities and included guidance on preventing ESD-related events.

However, in more recent years, the use of flammable anesthesia has decreased, and the NFPA dropped its guidance on controlling ESD from NFPA 99. Simultaneously, the use of sensitive electronic devices and electronic data has dramatically increased, creating new ESD-related risks. Moreover, the use of synthetic materials, such as bedding and gowns, increased the electrostatic charges being created in these environments. With NFPA dropping its guidance and these new risks emerging, facility managers were left with problems and nowhere to turn for help.

In response to this need, the International Electrotechnical Commission (IEC) published in 2018 IEC 61340-6, “Electrostatics – Part 6-1: Electrostatic control for healthcare – General requirements for facilities”³, which provides technical requirements and recommendations for controlling electrostatic phenomena in healthcare facilities, including requirements for equipment, materials, and products used to manage static electricity.

With support from members of the IEC committee, the ESDA decided to create a guidance document that delved deeper into this topic, provided more technical background on the nature of the risks involved, additional guidance on the mitigation measures that can be used, and descriptions of programs that can be implemented to ensure proper implementation of these recommendations. This new technical report, TR29 “Guidance for Control of Electrostatic Hazards in Healthcare Facilities”⁴, was released this year and provides a comprehensive review of the nature of the risks and the scientific support to justify the implementation of the recommended mitigation measures.

Causes of ESD in Healthcare Facilities

TR 29 provides a comprehensive description of how static charges are generated to provide the reader with a better understanding of how to minimize and control static charge generation. Some common sources of static charge generation in a healthcare facility are shown in Figure 1.

Table 1 provides some examples of the voltage that can be generated in some typical activities that occur in a healthcare facility. Table 2 provides the levels of concern for the various risks of concern in a healthcare setting. As you can see, common activities in a healthcare setting can easily generate electrostatic charges that are far in excess of levels of concern.

Table 1: Examples of static generation voltage levels

Table 2: Voltage levels of concern in a healthcare environment

Risks Addressed in ESDA TR29

TR29 addresses the most common risks associated with ESD in the healthcare environment. As previously mentioned, there are now risks associated with the use of electronic equipment and data. The risks addressed, depicted in Figure 2, include:

• Disruption/loss of function of medical devices: Medical instruments, such as MRI machines, ventilators, and infusion pumps, are highly sensitive to ESD. A discharge can cause these devices to malfunction or fail, potentially leading to incorrect diagnoses or treatment interruptions. For instance, an ESD event could disrupt the operation of a heart monitor, leading to false readings that might cause unnecessary alarm or, conversely, a lack of response to a genuine emergency.
• Disruption/loss of data: ESD can corrupt electronic data, impacting patient records and diagnostic results. This can lead to delays in treatment and errors in patient care. For example, if an ESD event occurs while updating a patient’s electronic health record (EHR), it could result in the loss of critical information, such as medication allergies or recent test results, which are essential for making informed medical decisions.
• Shocks to personnel: Patients and healthcare personnel can experience painful electrostatic shocks. These shocks can cause involuntary movements, which may lead to accidents or injuries, especially in critical care environments. For example, a patient receiving an intravenous injection might jerk their arm due to an ESD shock, potentially causing the needle to dislodge and leading to further complications.
• Contamination caused by electrostatic attraction (ESA): ESD can increase the deposition of microorganisms onto charged surfaces, contributing to hospital-acquired infections. This is particularly concerning in sterile environments like operating rooms and intensive care units. For instance, if ESD causes dust particles carrying bacteria to settle on surgical instruments, it could increase the risk of postoperative infections.
• Ignition of flammable materials: Although the use of flammable substances in healthcare has decreased, the risk of fires and explosions due to ESD remains, especially in laboratories and areas where oxygen is used. For example, in a laboratory setting, an ESD event could ignite volatile chemicals, leading to a fire that endangers both staff and patients.

Prevention of ESD in Healthcare Settings

Preventing ESD in healthcare settings requires a multifaceted approach. The mitigation measures recommended in TR29 include:

• Static control flooring/footwear/mobile equipment: Installing proper static control flooring in critical areas can help dissipate static charges from personnel and mobile equipment, such as hospital beds and IV carts. This is particularly important in operating rooms and laboratories. Also, static control tiles or carpets can be used in areas where sensitive electronic equipment is frequently used, such as radiology departments. Static control flooring can also be used in areas where data is entered, transferred, or stored.
• Equipment grounding: All electrical/electronic medical equipment should be properly grounded to prevent ESD. As mentioned above, this can also include grounding mobile equipment through the use of a drag chain or conductive wheel in combination with a static control floor.
• Low-charging and dissipative materials: Low‑charging relates to how much charge is generated upon contact and separation of the material from itself or other materials. Many patient care items are available with additives or treatments that make them low-charging. Conversely, untreated versions of these items are typically made of synthetic textile materials that are electrically insulating and can potentially acquire significant electrostatic charge. Also, applying antistatic sprays to surfaces can help reduce the generation of charges. For instance, antistatic sprays can be applied to synthetic garments to reduce charge generation and minimize the risk of ESD.
• Ionization: Ionizers can be used to neutralize static charges in the air and on insulative items, such as plastic packaging. Ionizers emit ions that attach to charged particles, neutralizing them and preventing ESD. Ionizers are generally useful for spot applications. For example, ionizers can be used to neutralize the static charge that is generated when surgical device packages are opened or at entrances to surgical suites to help remove ESA-attracted particles from personnel garments.
• Humidity control: Maintaining a relative humidity level of 40-60% can help reduce static electricity. Dry environments are more prone to ESD, so humidifiers can be used to maintain optimal humidity levels. For example, in a hospital ward, humidifiers can be strategically placed to ensure that the air remains sufficiently moist, reducing the likelihood of ESD events. There is also strong evidence that controlling humidity in this range has health benefits for occupants and can help reduce infections from airborne contaminants.
• Static control seating: The routine movement of a person seated in a chair or moving the chair across the floor can generate significant static charges. Using static control chairs in combination with a static control floor can be an effective means of removing those charges, which would be helpful in areas such as computer workstations.

Defined Risks and Suggested Mitigation by Areas

The ESD risks in a healthcare facility will vary depending on the area of the facility. TR29 provides a section that defines the inherent risks by type of area within the facility and the recommended mitigation measures to take for those areas. The guidance is defined for:

• Public spaces/waiting areas
• Administrative and office areas
• Server rooms and data closets
• Clinical examination rooms
• Patient wards
• Acute care wards
• Diagnostic areas
• Surgical and operating suites
• Laboratories
• Pharmacies

ESD Control Programs

TR29 provides a sample of a control program that a healthcare facility can implement to reduce the risk of ESD hazards. Modeled after ANSI/ESD S20.20, this guidance includes suggestions for:

• Electrostatics coordinator: Having a designated person to oversee the program. This person should have basic knowledge of electrostatics.
• Staff training: Healthcare personnel should be trained on the importance of ESD control and the proper use of ESD prevention tools. This training could be as simple as having an understanding of TR29 since it provides a comprehensive background on the science of ESD, the nature of the risks, and details on mitigation measures. Also, regular awareness campaigns can help reinforce the importance of ESD control and encourage compliance with ESD prevention protocols. For instance, posters, such as the one shown in Figure 3, and informational brochures can be distributed throughout the healthcare facility to remind staff of best practices for ESD prevention.

• Defined controls by facility area: The sample program includes a matrix that can be used to define the mitigation measures to be used in the various areas of the facility
• Compliance verification: The sample program also provides measures to use to ensure mitigation measures are functioning properly.
• Recordkeeping: It is also recommended that the facility keep records of the mitigation measures employed, any records of their compliance verification, and reports of incidences of ESD events.
• Consultation: Healthcare facilities can benefit from consulting with ESD experts to develop and implement effective ESD control programs. These experts can provide guidance on best practices and help identify potential ESD hazards. For example, an ESD consultant can conduct a thorough assessment of a hospital’s ESD control measures and recommend improvements. ESD experts can also provide specialized training programs for healthcare personnel. These programs can cover advanced ESD prevention techniques and the proper use of ESD control tools.

References

1. Guest, P. G., Sikora, V. W., and Lewis, Bernard, Static Electricity in Hospital Operating Suites: Direct and Related Hazards and Pertinent Remedies, report, 1953, Washington D.C.
2. National Fire Protection Association, Standard for Health Care Facilities (NFPA Standard No. 99), 2002.
3. IEC 61340-6-1:2018, Electrostatics – Part 6-1: Electrostatic control for healthcare – General requirements for facilities, International Electrotechnical Commission (IEC), 2018.
4. ESD TR29.0-01-24, ESD Association Technical Report for the Protection of Electrostatic Discharge Susceptible Items – Guidance for Control of Electrostatic Hazards in Healthcare Facilities.