Electromagnetic Fields

Having been invented more than half a century ago, radar detection is certainly a very popular form of technology. Today, radars have applications in the air travel, weather forecasting, defense, security, and law enforcement.

But radar systems work by transmitting high frequency electromagnetic signals. And electromagnetic fields (EMF) are claimed to cause some serious health issues in those constantly exposed to these high frequency waves. However, those who need to be concerned the most about radars are the people who have to constantly work dangerously close to them.

There are suspicions that radars can cause reproductive issues, cancer, cataracts and even behavioral issues among kids. There are even statistics indicating that police who constantly use hand-held radar guns have elevated incidences of testicular cancer.

But as worrying as these health issues might sound, it is important to remember that there is a distinction between real and imagined threats of being exposed to radar technology. The electromagnetic spectrum is very broad, and each band of frequencies has a different impact on the body.

With this in mind, it is important to understand that some of the health issues ascribed to radar-based systems are specific to EMF frequencies this technology does not even use. For instance, frequencies of below 10Gz enter body tissues and get absorbed. The penetration of these frequencies is very shallow, and no worrying health effects should be expected from such exposure.

At What Point Do Radar Emissions Become a Health Concern?

Radar technology uses frequencies of between 300 MHz and 15 GHz. That means that there are radar frequencies that have no notable health impact on the body (those below 10 GHz).

However, even for frequencies above 10 GHz, the amount of exposure a person experiences plays a very significant factor in determining whether the victim will suffer any adverse health effects or not.
The amount of radiation the body absorbs is measured in form of Specific Absorption Rate (SAR), whose unit is watts per kilogram (W/kg). Negative health effects start to set in when SAR value reaches 4 W/kg.

The power density of the radar’s EMF radiation can also offer some insight into how much of this dangerous exposure will get absorbed by the skin. This intensity is measured in watts per square meter (W/m2). Basically, a combination of radar frequencies above 10 GHz and power densities of more than 1,000 W/m2 is what results in health effects such as skin burns and cataracts.

Police radars emit some of the least amounts of EMF radiation. But large space tracking radars can emit many kilowatts of of this harmful energy.

What Affects the Degree of Harm Radar Systems Can Cause to Humans?

Issues like the direction of the energy being transmitted, and the number of wave pulses being sent off in a given amount of time often affect how much of a health threat these systems pose.
In any case, many radars keep changing their directions, while many of the most dangerous of these systems are often installed in restricted areas.

This blend of factors has been known to lower the potential harm of radar waves by a huge degree, usually by a factor of over a 100. Various Types of Radar Systems, and The Impact of Their Emissions on Health

Air Traffic and Weather Radars

Based on the above factors, air traffic control radars, despite sometimes emitting waves of over 100 kW, pose little threat to the public since their waves are not accessible to people on the ground. Furthermore, they have an average power of a few hundred watts.

And so, they should not pose any threat to public health under normal usage conditions. The same goes for weather radars, which are often found in the same place as air control radars, places typically inaccessible to the general public.

Military Radar Systems

Military radars blast beams at powers of 1 MW (1,000 kW) or greater. While such quantities of radiation sound lethal, these radars radiate their beams over a large area, which lowers the power densities to as low as 10 W/m2. And that is within where the systems are located; areas not accessible to the public.

Beyond these areas, the emissions are even a problem to identify. So, these radar systems are not a health concern either – under normal circumstances. Ironically, military radars installed on aircraft pose the greatest amounts of health risks as the ground crew regularly gets close to these systems.

Although their peak power is nowhere close to that generated by large military radars, these systems can have high relative densities of up to 10 kW/m2.

Marine Radars

Marine radars, installed on small boats on larger sea vessels can peak at 30 kW. Their average power, however, can be anywhere from 1 to 25 watts, and the power density within a meter is less than the recommended exposure levels at under 10 W/m2.

Police Radar Guns

The hand-held radar guns used by police use very low power, which is not even harmful to the police using them. But fortunately for car owners. with the best radar detector, these low radiations are still clearly detectable from a distance.

Although there are studies trying to link cancer to the use of these radars, the evidence that this is what actually happens is underwhelming. Definitive studies are required before this link can be definitively proven.

What Exposure to Excess Radiation Can Do to the Body?

Exposure to too much radar radiation has been shown to reduce mental abilities and increased body tissue temperatures by over 1 degree Celsius. These levels radiation have also been linked to the development of cataracts.

These effects are the basis for the protective measures taken to keep the public safe from the radiation radar systems generate.
When the RF levels are low, it is claimed that they can result in decreased calcium ion mobility.

However, there is no adequate evidence proving why this should be taken into consideration when coming up with ways to safeguard the public against radars.

Additionally, exposure to pulsed RF fields of frequencies of about 200 MHz and 6.5 GHz can be audible in form of clicking, hissing, clicking, and popping sounds. With continued exposure, individuals may suffer from stress.

When RF frequencies are less than 100 MHz, charges can be induced on metal objects close to the radars. People close by can experience burns, shock and high tissue absorption rates. However, these frequencies are rarely used. Additionally, when they are used, wide beams are never used, which makes their impact even less of a public health concern.

Other Effects

Electromagnetic interference can also occur due to these radar emissions. But even when such disruptions occur, the level of human exposure is typically well below levels that can cause harm to humans. However, this interference can be an issue for people using pacemakers or hearing aids, which can be susceptible to the effects of this radiation.

A huge concentration of radars can also cause the ignition of flammable liquids and explosives due to the induction of currents. But this is rare, and environments where this might occur typically have measures in place to prevent such incidents.

What Is Being Done About Exposure to This Radiation?

WHO (World Health Organization) works with the Commission on Non-Ionizing Radiation Protection (ICNIRP), an NGO, to put in place guidelines on RF levels the public can safely be exposed to when setting up radar systems. At the moment, these guidelines ensure that the public is exposed to emission levels that are 25,000 times below those known to cause health problems.

However, there are people who have to get close to these systems. These people have to take protective measures so that they can get closer than is safe without risking any adverse health risks. This includes putting on gloves, safety shoes and so forth.

Still, it is important to use clothing that is obtained from the right sources since there is protective clothing in the market that claims to provide the required protection but does not. Other control measures are also employed. They include alarms, shielding, warning signs, and limitation of access to the radar systems.

To Sum Up

Radars generate waves that can make the molecules on the skin to vibrate and heat up. But a minimum radiation threshold has to be attained before these adverse health effects are noted. Even then, there is nothing to be concerned about if the tissue temperature does nor rise by more than 1 degree Celsius.

Otherwise, claims that the radiation blasted by radar systems can cause cancer are not founded on any hard evidence. Definitive research will be needed before such a clear link between radar systems and cancer can be clearly established.