The Risk to Your Cardiac ICD & Pacemaker
Effects of the Strong Electromagnetic Fields Found in Your Workplace
Caution to employees and employers who have implanted cardiac devices! The electrical and/or radio communications equipment found in your workplace may cause harmful interference with your ICD or pacemaker. In the last decade there has been increased public concern about exposure to low-frequency electromagnetic fields (EMF) from power lines and to radio wave fields from cell phones. There are special concerns for exposure of people with cardiac assisting devices such as an ICD or pacemaker. These devices may be inactivated or made to operate improperly upon exposure to strong magnetic fields or strongly emitting radio transmitters.
An Implantable Cardioverter-Defibrillator (ICD) is a device that is implanted under the skin of patients that are at risk of sudden death due to ventricular fibrillation. The purpose of these devices is to provide defibrillation if the heart enters a potentially lethal rhythm.
A pacemaker is a medical device designed to regulate the beating of the heart. The purpose of an artificial pacemaker is to stimulate the heart when either the heart's native pacemaker is not fast enough or if there are blocks in the heart's electrical conduction system preventing the propagation of electrical impulses from the native pacemaker to the lower chambers of the heart.
Low-frequency electromagnetic fields (EMF) are generated when an electrical current pass through a wire or electrically operated device. These fields can sometimes interfere with implanted cardiac devices known as ICDs and pacemakers. Some of the equipment that may cause interference with ICDs and pacemakers are devices found in an industrial environment. These include drive motors (especially DC driven), arc welders, battery-powered, cordless power tools, drills, and electric screwdrivers.
Radiofrequency fields (RF) are those radio wave signals that are generated by devices like cellular phones, CB radios, broadcast towers, etc. Both of these fields can potentially interfere with cardiac assist devices such as cardiac pacemakers and ICDs (implantable Cardioverter defibrillators). Although most environments do not pose EMF risks, certain types of electrical equipment may produce levels of EMF that can temporarily interfere with ICD or pacemaker performance. The result, asynchronous (irregular) pacing of the heart by the implanted cardiac device, is potentially life-threatening.
Items producing EMF or RF fall into the following broad categories:
· Personal Items
· Kitchen and Household Items
· Do-It-Yourself Items
· Entertainment Items
· Travel and Environment
· Medical Procedures
According to the Guidant Corporation, a major manufacturer of ICDs and pacemakers, the following types of equipment, some of which are found in the home, are potentially hazardous for those people who have an implanted ICD or pacemaker. See the table below.
Equipment with Potential to Interfere with Cardiac Devices
Type of Device
Cell phones - In certain cases, a cellular phone could affect an ICD or pacemaker’s operation if it is closer than 6 inches (15cm) to the implanted cardiac device. This interaction is temporary, and moving the phone away from the implanted cardiac device will return it to proper function.
· Maintain a distance of at least 6 inches (15 cm) between the cellular phone and the implanted cardiac device; if the phone transmits more than 3 watts, increase the distance to a minimum of 12 inches (30 cm)
· Hold the cellular phone on the opposite side of the body from the implanted cardiac device
· Don’t carry a cellular phone in a breast pocket or on a belt if it places the phone within 6 inches (15 cm) of the implanted cardiac device
Walkie-talkies, repeater stations, broadcast towers
Maintain a distance of at least 12 inches (30 cm ) between the radio device and the implanted cardiac device; if the phone transmits more than 3 watts, increase the distance to a minimum of 12 inches (30 cm
Arc welding equipment
Recommend maintaining at least a 24-inch (61-cm) separation at all times between the cables, arc, transformer, and your implanted cardiac device.
Car engine repair
Alternators create magnetic fields, which could potentially deactivate or temporarily inhibit an ICD. Recommend maintaining at least a 12-inch (30-cm) separation at all times between the motor and your implanted cardiac device. Avoid leaning directly over the alternator of a running car engine.
Running motors and alternators
Small motor repair
CB/police radio antennas
Remote controls with antennas
Radio frequency transmitters
TV or radio towers
Magnetic resonance imaging (MRI)
Microwaves built before 1971
Recommend maintaining at least a 12-inch (30-cm) separation at all times between the motor and your implanted cardiac device.
Testing the Workplace for EMF and RF
One way of assuring employee safety of those with cardiac devices is to test the workplace in which they work for both electromagnetic and radio wave field strength. This is done by surveying the facility with specialized meters that will detect the location and strength of those fields. The ensuing results can serve as a “roadmap” to ensure the safety of the employee. Those areas determined to be problematic can be dealt with by either shielding of the source(s) or avoidance of those areas known to exceed safe guidelines (see below).
Real World Examples of EMF Patients/Industries
The following industrial facilities were tested for Electromagnetic Fields because one or more of their employees have a cardiac implanted device:
Ø A major box and cardboard container manufacturer
Ø A liquor manufacturer and distributor
Ø A label manufacturer
Ø A regional transportation system’s bus garages, broadcast towers and repair facilities
Ø An oil and machine filter manufacturer
Ø A municipal sewage and sludge treatment facility
What these facilities have in common is an employee who is working in or returning to the facility with an implanted cardiac device and facility machinery capable of exceeding recommended guidelines for electromagnetic field strength or for strong field radio communications equipment.
Setting Safe Exposure Limits
The pacemaker manufacturers and several non-governmental bodies have created voluntary standards for exposure to EM and RF radiation sources for those with and without cardiac implants. Those standards include those of the Federal Communications Commission, the Food and Drug Administration (FDA) and the American Conference of Governmental Industrial Hygienists (ACGIH).
What about my workplace?
Do you have high energy equipment and/or strong radio transmitters?
with an implanted cardiac device?
If the answer to both of these questions is “yes”, then you may want to evaluate the electromagnetic and radiofrequency fields in your workplace in order to protect your most valuable assets, your employees.
Stuart Bagley is a senior consultant at IAQ Services of Indianapolis, IN, (317) 598-0148
(800) 862-9655, on the web: www.IndoorAirSite.com
 Sources of Electromagnetic Interference (EMI) For Pacemakers, Implantable Cardioverter Defibrillators (ICDs), and Heart Failure Devices (CRT-Ds) Sources, Guidant Corporation (now Boston Scientific), May 2003, www.Guidant.com