SAR and Mobile Phone Safety
Mobile Phone Safety and Compliance with Safety Standards
All mobile phone models sold in Australia must comply with the Australian Government’s radiation exposure standard.
The Australian Communications and Media Authority (ACMA) requires industry to comply with the Human Exposure Standard, which applies exposure limits set by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA).
The ARPANSA Standard specifies exposure limits of radiofrequency electromagnetic energy (RF EME) which users absorb from the handset. This is known as the Specific Absorption Rate (SAR), which is the rate at which RF EME is absorbed by body tissue.
The ARPANSA safety standard is designed to protect people of all ages and health status against all known adverse health effects from exposure to electromagnetic energy (EME) from mobiles, base stations and other wireless devices.
The SAR limit in Australia for mobile phone handsets is 2W/kg of tissue averaged over 10 grams. The limit includes a significant safety factor.
Mobiles must comply with the SAR limits before being supplied to the Australian market.
Where to find information about your mobile’s compliance with safety standards
The printed quick start guides provided with mobile phones carry notification about how mobile phones are tested for compliance with safety standards when a phone is held close to the body, such as when placed in a pocket. The notification is easily found in the short, quick start guides for each phone model.
The notification is intended to show transparency about how each phone model is tested when used close to the body to meet the exposure safety limits – they are not a “hidden safety warning”.
Manufacturers also provide this information on their web sites and usually as part of information in the actual device.
Like most electronic consumer goods, it’s important to be familiar with how each model is tested for compliance with safety standards.
Phones are tested when used against the ear and for when body worn
Mobile phone guides advise owners on appropriate use for various situations. The notifications describe distances that mobile phones are tested at maximum power away from the body (not the ear or head).
The test procedures measure each model of phone in the usual position held to the ear when making phone calls – there is no added separation distance used in these tests.
When used next to the ear no separation distance is required to meet the exposure limits because phones are designed to have the antenna far enough away from the head when making a phone call – either by the way the phone is angled in normal use or where the antenna is positioned in the particular phone model.
In the case of most smartphones, the antenna is at the back of the phone, at the base near the microphone and well away from the ear and head when in use.
For use when not held to the ear, phones are tested at distances intended to represent belt-clips, holsters or similar accessories or at a small distance from the trunk of the body to simulate the effect of clothing or the intended type of use.
Is it ok to carry a phone in a pocket close to your body?
Consumers sometimes ask: “Is it OK to carry a phone in my pocket?” Putting your mobile phone in your pocket is an appropriate way of carrying a mobile phone, although you should be aware of how phones are tested for compliance at maximum power levels using separation distances.
If a consumer does not use a body-worn separation distance, safety is not compromised because the safety standards have large built-in safety margins, which protect the user. This is why this is not a safety warning.
A mobile model’s Specific Absorption Rate (SAR) shows that it operates within the safety standard limit. It is obtained from a compliance test with the handset operating at maximum power output. However, in everyday use mobile phones operate at much lower power levels, adapting to the minimum power required to make a call to preserve battery life, maximise call time and avoid network interference.
In Australia, the SAR limit for the general public is set at 50 times (5000 per cent) below known health risk levels, such as acute exposure to sensitive organs like the eye, and for workers the added safety factor is 10 times (1000 per cent). Therefore, even if a consumer was exposed above the general public limit they would not break the occupational limit.
To ensure mobile phones are safe, exposure standards take a worst case scenario – a phone operating at maximum power output – whereas in real life everyday use phones almost never work at maximum power output.
Mobile phone SAR measurement
This short video clip takes a look inside a SAR measurement laboratory where a mobile phone is being put through the SAR testing process. Video courtesy of Ericsson.
What do independent government safety experts say about exposures above safety limits?
In a recent review of RF safety standards in the USA the Federal Communications Commission (FCC) said because of these safety factors, exposures above the limits do not pose a health hazard:
“The limit is readily justified when it is based on known adverse health effects having a well-defined threshold, and the limit includes prudent additional safety factors (e.g., setting the limit significantly below the threshold where known adverse health effects may begin to occur). Our current RF exposure guidelines are an example of such regulation, including a significant ’safety’ factor, whereby the exposure limits are set at a level on the order of 50 times below the level at which adverse biological effects have been observed in laboratory animals as a result of tissue heating resulting from RF exposure. This ‘safety’ factor can well accommodate a variety of variables such as different physical characteristics and individual sensitivities – and even the potential for exposures to occur in excess of our limits without posing a health hazard to humans.”
Are mobile phones with a low SAR rating safer?
The SAR value reported for each mobile phone overstate real life exposure levels because all models are tested at maximum power levels to ensure they meet exposure standards.
They are tested to indicate the worst case exposure in a laboratory test situation, however, mobile phones rarely operate at maximum power levels during everyday use.
To avoid network interference, improve battery life and available call time, mobile phones constantly adapt to the minimum power required to maintain a quality call.
If people are concerned about exposure is there anything they can do?
Although current scientific research does not indicate mobile phone use is associated with harmful health effects there are simple things that can be done to substantially reduce exposure if people have concerns.
“The most effective way to reduce exposure is to increase the distance between the mobile phone and the user,” says ARPANSA. See: http://www.arpansa.gov.au/mobilephones/index.cfm
Other things that can be done to reduce RF EME exposure from mobile phones are:
- not using a mobile phone when a fixed-line phone is available
- sending a text message or instant message instead of making a voice call
- limiting the duration of calls
- making calls where reception is good.
ARPANSA says to be aware the some so-called protective devices may not reduce RF EME. These products are attached to the handset and take the form of shielded cases, earpiece pads/shields, antenna clips/caps and absorbing buttons.
ARPANSA says: “Currently there are a number of protective devices available on the market which claim to protect the mobile phone user from RF EME emissions. Scientific evidence does not indicate any need for such devices since their use cannot be justified on health grounds and their effectiveness in reducing exposure in everyday use is unproven.”
More information on SAR
The Mobile Manufacturers Forum (MMF) has the SAR-Tick Label to help consumers learn more about national and international exposure standards for their mobile phones and wireless devices.