On No, not another cellphone radiation reducing gizmo!

Stuart Corner
Monday, 23 May 2011 09:49

Opinion and Analysis

There's yet another device on the market claiming to protect your noggin from all the nasty radiation that spews out of your cellphone every time you clamp it to your ear and chat away. This one backs up its claims with a comprehensive test reported from a NATA accredited laboratory. But as usual the claims don't stand up to close scrutiny.

This one, from www.cellsafe.com.au, is for the iPhone4 and takes the form of a silicone case that, according to Cellsafe's ad is "embedded with an RF module antenna [that] deflects radiation away from your head and body."

Cellsafe makes the claim that the case reduces radiation by up to 74.2 percent and increases signal strength. Since signal strength and radiation are one and the same that's a pretty impressive claim. But Cellsafe has had the device tested by an independent NATA accredited test laboratory, EMC Technologies, and is quite happy to make the full report and a summary available for download from its website.

The full report would I suspect be double Dutch to anyone but a qualified RF engineer or some similarly skilled. But you don't need to delve that deep to see that the Cellsafe gizmo is nowhere near as good as it might first appear when it comes to reducing brain-fry.

Yes, the EMC report does quote 74.2 percent reduction in specific absorption rate (SAR) (with a margin of error of plus or minus 19.5 percent) but guess what? That is only at 900MHz - the frequency used for 2G and in some parts of the country for 3G by Optus and Vodafone. At Telstra's 3G frequency of 850MHz the reduction is only 38.8 percent (± 19.5 percent) and at the other 3G frequencies of 1800MHz and 2100MHz it is respectively 18.0 percent and 15.4 percent, again with an error margin of ± 19.5 percent. So there is fair chance it's not doing much at all to cut radiation to your brain.

But what about this claim for increased signal strength, which Cellsafe insists is also based on a test result? If that's the case it has not provided this result. The EMC test for radiation to the head focussed solely on how use of the case affected radiation levels in the head position when the phone is held to the ear. No connectivity or call quality tests were performed, and the test report states specifically that the effect of the case on transmitted power is not known.

But hey, who's going to read all that stuff? Certainly not the "RF exposure category" identified in the test report: "General Public/Unaware User"!