"That does not reflect reality today for the vast majority," said analyst Avi Greengart of Current Analysis.
You might expect phone makers to use the closer standard, given how many people carry their phones in their pocket. Vendors know this: They put a lot more effort into slim designs and scratch-resistant glass than into, say, Kid Rock and Spice Girls ringtones. Yet when it comes to radiation testing, they're still stuck in the last decade.
Take the Health and Safety Warranty Guide for the Samsung Galaxy S6 Edge, for example.
"For body-worn operation, this device has been tested and meets FCC RF exposure guidelines when used with an accessory that contains no metal and that positions the mobile device a minimum of 1.5 cm from the body. Use of other accessories may not ensure compliance with FCC RF exposure guidelines," the guide says.
Samsung doesn't say what kind of accessory it's talking about here, but unless it counts purses and backpacks as accessories, the implication is clear: Holster up like a cable guy.
Or check out the safety page from the Motorola Moto G manual: "When using the mobile phone next to your body (other than in your hand or against your head), maintain a distance of 1.5cm (3/4 inch) from your body to be consistent with how the mobile phone is tested for compliance with RF exposure requirements." If you use a case or holder, make sure it doesn't have any metal, Motorola adds.
The user guide for an LG G4 says the phone was tested for "typical body-worn operations," with 1 cm between the body and the back of the phone. And the manual for the HTC One M9 from Sprint comes right out and invites us on a walk down memory lane: "To ensure that RF exposure levels remain at or below the tested levels, use a belt-clip, holster, or similar accessory" to keep the sleek 2015 smartphone at least one cm from your body. They don't say which is best, nor do they recommend the best Bryan Adams albums to load on your Rio.
Apple, on the other hand, is either too realistic or too vain to endorse a fashion that the iPhone helped to kill. It uses the 5mm rule.
The FCC doesn't say a phone tested closer to the body is safer than one tested farther away, and the emissions limit is the same for both. Devices either exceed the allowed radiation level or they don't.
Yet the language in some user manuals implies that separation distance does matter if you're worried about radiation. Under the heading, "Can I minimize my RF exposure?" the LG G4 user guide says, "You can place more distance between your body and the source of the RF, as the exposure level drops off dramatically with distance."
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