A cell phone case for reducing cell phone radiation

Pong Research offers a case that it says will reduce the amount of cell phone radiation that your head will absorb during a call. Surprisingly, it appears to work.

Kent German Former senior managing editor / features
Kent was a senior managing editor at CNET News. A veteran of CNET since 2003, he reviewed the first iPhone and worked in both the London and San Francisco offices. When not working, he's planning his next vacation, walking his dog or watching planes land at the airport (yes, really).
Kent German
7 min read

The Pong iPhone 4 case Pong Research

Outside of the battle between iPhone fans and Android advocates, few debates in the cell phone world are more divisive than that over whether the radio frequency (RF) energy emitted by cell phones is harmful. Though the industry and some members of the scientific community insist that there is no danger, other researchers and a growing number of public officials believe that there is cause for concern. No consensus exists, and as CNET has reported, any agreement or firm evidence may not come for a long time, if it does at all.

In the meantime, some CNET readers will feel more comfortable erring on the side of caution. If you're concerned, you can use a headset, text instead of talk, and limit calls when your carrier signal is low (more RF energy is emitted when a phone is working harder to reach a tower). Yet, since that advice isn't always practical, Pong Research has another solution, with a case that is designed to refocus RF energy, or radiation, away from your head while not reducing signal strength. So in other words, you can use your phone just as you normally would.

If you think that sounds like pseudoscience, I don't blame you. Honestly, I've never taken seriously the cheap radiation "shields" that you can find online. Usually nothing more than tiny stickers, I didn't believe that they did anything, except spread a false peace of mind. Few of the products backed up their claims with solid proof, and, even worse, some can actually interfere with your cell phone's signal. That's why I was pretty skeptical when I first heard of the Pong case. But as it turns out, the company has done its homework.

Related links
Pong releases 'antiradiation' BlackBerry case
Complete ratings: Cell phone radiation levels
Cell phone radiation: Harmless or health risk?
The trouble with the cell phone radiation standard
Cell phone radiation: A self-defense guide (FAQ)
Cell phones and the radiation risk (roundup)

The case itself
One of the best things about Pong's product is that it serves a very functional purpose, regardless of whether it has an effect on your phone's radiation level. You also can use it as a regular case that will protect your handset from its daily grind and the occasional drop to the floor. You can get the case in a few colors and styles, though Pong supports only a handful of smartphones at the time of this writing. I used the case for the iPhone 4, but it's also available for the previous iPhone models, most BlackBerry Curve and Bold handsets, the Motorola Droid X2, and the HTC Evo 4G. Pong says it will support more phones in the coming months.

Made of a hard polycarbonate called Lexan, the case snaps easily onto the iPhone 4. The fit is secure, though I wish the top rim of the case wrapped slightly around the handset's bezel. You might think that's simply a matter of aesthetics, but I'm worried that the iPhone's display could hit the ground (and possibly break) if it were to fall face-first. On the upside, though, the case isn't overly designed, with just a chevron pattern on the back.

The image on the left shows the near-field radiation pattern without the Pong case on an iPhone 3GS, and the image on the right shows the pattern with it.

What it does
Shannon Kennedy, Pong's president and CEO, said the purpose of the case is not to cut down on the amount of RF energy that comes from a phone (again, that would make the phone work harder), but rather to redirect and redistribute it away from your head. Normally, when you're on a call, the cell phone emits RF energy in all 360 degrees from the antenna with up to 50 percent going directly into your head.

With the Pong case, however, an antenna inside the case interacts with the phone's antenna and funnels the RF energy away from your head and out the back of the phone. Kennedy says the goal is to reduce the amount of radiation absorbed by the head by at least 50 percent and up to 95 percent. What's more, as a phone shifts frequency bands and power levels, the case will adjust to the increased or decreased radiation level accordingly.

Though Kennedy says his company isn't making claims about whether cell phone radiation is absolutely dangerous, he doesn't buy the notion that it's completely safe, either. "It's no longer controversial that [RF energy] has an effect on your brain," he said when citing a study from earlier this year that found cell phone exposure was associated with increased metabolism of glucose in the region of the brain closest to the antenna. As he explains it, the Pong case is simply a way to reduce excessive exposure while research continues. "There's no consensus on the long-term health effects," Kennedy says. "Until we know, we're saying, 'Don't take a chance on whether it's negative or not'...We're pro-cell phone, but we're about making a safe device safer."

So does it work?
That, of course, is the big question. And when Pong first introduced its product back in 2009, some gadget reviewers weren't impressed. Wired magazine, for instance, first called Pong's product "snake oil." Yet, the publication reversed course a few weeks later after it tested the product at Cetecom, an FCC-certified lab in Milpitas, Calif., that tests cell phone radiation levels for handset manufacturers.

During such a test, the phone is positioned next to a dummy human at close to, though not exactly, the distance at which a real person would hold a cell phone. The head's shell is plastic, but inside it's filled with gel to resemble the density of a human brain. A simulated call is then placed and equipment measures the highest Specific Absorption Rate, or SAR, caused by the phone's emissions (for an alternative look at the testing process, see my look inside Sprint's testing labs in Kansas). According to the tests that Wired observed, the Pong case reduced the SAR of the head by 64.7 percent, from 1.19 watts per kilogram to 0.42 watt per kilogram.

Unfortunately, I couldn't go to down to Cetecom this week, but Kennedy sent along test results that his company has had run at the same lab. With AT&T's iPhone 4, for example, the Pong case reduced the SAR and the Total Radiated Power or TRP (a measure of how much power is radiated by an antenna) absorbed by the head as follows:

iPhone 4 SAR tests
SAR without case (in w/kg)
SAR with case (in w/kg)
Percent reduction
Percent below FCC limit (1.6 w/kg)
GSM (2G)

iPhone 4 TRP tests
TRP without case (in dBm)
TRP with case (in dBm)
TRP change (in dBm)
GSM (2G)

From the user's perspective, you should notice no difference in the performance of your phone. Because of the case's construction, you may notice that some handsets don't feel as hot after a long conversation, but I didn't detect any difference in signal strength, audio quality, or data reception.

Should you buy it?
That all depends on your comfort level with the whole debate. If the prospect of cell phone radiation concerns you, then it's not a bad idea. Not only will you get a case for your handset (something you need anyway, particularly if you own an iPhone 4), but you'll be reducing SAR exposure at the same. On the other hand, if you aren't worried about RF exposure, then you should move on. That is, unless you're buying a case and just fancy Pong's design. But either way, it can't hurt.

On the other hand, there are important caveats to remember when thinking about a phone's SAR. There is no guarantee that a phone with a lower SAR is inherently safer. The SAR listed in a phone's user manual and in CNET's cell phone radiation charts is the highest possible number that the handset reached during FCC tests. During a call, however, the phone may never reach that amount and the SAR can change constantly depending on the frequency used and your distance to the tower. So while reducing your phone's SAR may make you feel better, we don't know that it really is safer. Kennedy acknowledged that fact in our interview and recommended that users think about a phone's TRP instead of relying just on the SAR alone. But even then, there is no guarantee that Pong's product will prevent any detrimental health effects of cell phone radiation if such effects are ever found.

Where to buy
In addition to buying the case from Pong directly, you can get it from other online retailers. At $49.99 per case, some people may find the product prohibitively expensive. But when you consider that some pretty average iPhone cases cost up to $39.99 (products by noted fashion designers can go even higher), Pong isn't asking for many more dollars.

Where Pong goes from here will be interesting to watch. The company has been awarded four patents and it has seven more pending. Not surprisingly, though, Kennedy says the cell phone industry has yet to comment on the need for his product or even acknowledge it. "Their industry's response has been consistent with their response to the [cell phone radiation] debate," he said. "So until the industry can demonstrate that cell phones are completely safe, you can take this precaution."