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On Call: Which cell phone radiation level is correct?

When the same cell phone has a different SAR, how do you know which one is correct? In this week's On call column, CNET's cell phone editor helps you make sense of it all.

Samsung Soul Samsung

Q: I'm thinking of buying the Samsung Soul and I'm concerned with its radiation level. But when I looked at the user manual there were multiple SARs listed. Is this typical and how do I know which listing is right?
- Rich

A: It's not a matter of which listing is right since it is very common for a single handset to have multiple SARs. For both GSM and CDMA phones, the radiation level will vary by transmission band, the testing position (at ear vs. at body), and the testing body that reported the results. In CNET's radiation charts we always list the highest at-ear SAR as tested by the FCC. I know that's a lot of qualifications, but the distinctions are important to understand.

I'm glad you mentioned the Soul since that phone is a great example of just how results can vary. First off, the Soul uses three GSM bands (900, 1,800, and 1,900) so it's likely that you're seeing a different reported SAR for each band. As I said before, all of the listings are correct, but for your situation one SAR will be more correct than the others. Of the three GSM bands the Soul uses, only the 1,900 band is used in the United States, so I would concentrate on that listing. Also, you'll want to make sure that the results are from the FCC, which conducts tests specifically for the U.S. market. If the results are form another body, such as the European Union's testing agency or Industry Canada, then you could see a different result.

If you have a quad-band phone that also uses the 850 band, which is used in North America, then you'll want to take note of that SAR as well. But here's here's another point to remember: your phone's SAR can change during a call as it switches between the 850 and 1,900 bands. Exactly which band it is using at a given time depends on a lot of factors beyond your control. So in short, you'll want to take note of both numbers. If one of them is too high for your comfort then you should take that into account when making a buying decision.

RIM BlackBerry 8820 Corinne Schulze/CNET Networks

Q: With all the news of cell phone radiation out there, can you offer advice on how to avoid or help eliminate the risk of radiation? Are there any products out there that really help? I currently use a AT&T Blackberry 8820, which does not have quite the highest radiation level, but I'm still worried, considering I use it just about 24 hours a day.
- James

I'm sure you've heard that last week the director of the University of Pittsburgh Cancer Institute warned his staff to "limit cell phone use because of the possible risk of cancer." A few readers have asked me about the warning and its significance, and while I lack medical training, I have to stress that it was not based on any published data that prove a link between cell phone use and cancer. In fact, it's contrary to numerous studies that have not found a link between the two.

In his memo, Dr. Ronald B. Herberman acknowledges that research is ongoing, yet he argues for taking precautions now. "Although the evidence is still controversial, I am convinced that there are sufficient data to warrant issuing an advisory to share some precautionary advice on cell phone use," he wrote. A paper that Herberman cosigned with 18 other pathologists, oncologists and public health specialists expressed a similar sentiment. "Studies in humans do not indicate that cell phones are safe, nor do they yet clearly show that they are dangerous," the paper said. "But, growing evidence indicates that we should reduce exposures, while research continues on this important question." According to Herberman, a forthcoming study from the World Health Organization, will provide more definitive data on the health effects or prolonged cell phone use.

So as you can see, James, we still don't know for sure one way or another. If this is an important issue to you I would suggest taking the following precautions, many of which Herberman recommends. First off, choose a phone with a low SAR rating. CNET lists the SARs for almost all current phones in our radiation charts. Secondly, use a headset or a speakerphone whenever possible in order to maximize the distance between the phone and your body or try sending a text message instead of making a call. And lastly, limit cell phone use for very young children.

iPhone 3G Corinne Schulze/CNET Networks

Q: Is it illegal to unlock an iPhone 3G and sell it? I know it's legal to do it on other phones. But the iPhone gets a lot of special treatment, so I feel like there is an exemption in the law.
- Mandeep

A: It's not illegal at all.

Q: I am new to cell phones, but I've just placed an order for an unlocked Nokia 6085. I am certain my phone will come without a SIM card, so how do I find one? And how do I know which SIMs will be compatible?

A: SIM cards are easy to find, but you'll need to make a decision first. If you're willing to accept a service contract with a carrier, then they'll provide you with a SIM card when you sign up. If you activate online, the carrier will send the card to you. But if you go to a carrier store, you can just tell then you're using your own phone. Finally, keep in mind that GSM carriers like T-Mobile and AT&T will support your unlocked 6085, but CDMA carriers like Sprint, Verizon Wireless, Alltel and US Cellular will not.

Nokia 6085 Nokia

Alternatively, if you'd rather get prepaid service, you can also visit a carrier store and buy a prepaid SIM. Such cards also are available from third-party cellular shops that are not affiliated with a carrier.

Q: I have a business contract with AT&T and recently bought a new Motorola phone to replace my current LG model. What is involved in swapping my SIM card?
- Bill

A: Switching SIM cards is very easy as long as your new LG handset is configured for AT&T service and you have an active account. Just remove the SIM card from the Moto phone--typically, SIM cards are located behind the battery--and pop it into the slot on the LG.

Once you make the switch, your new handset should be ready to go. If you bought the phone unlocked, there is a chance you'll need to program it with correct multimedia settings to send picture messages and browse the wireless Web. If that's the case, then you can get the settings from AT&T. But in either case, you'll be able to make calls right away.

Kent German, CNET's cell phones guru, answers your questions about cell phones, services, and accessories and reports on the state of the industry. Send him a question!. For past columns, check out the columns in the On Call archive