Sunday, May 15, 2011

Handphone Safety

Cell phone has become a standard thing to have now. Many people from various age have use it. People use cell phone to communicate in almost everywhere. There are several safety factor need to be considered when using a cell phone. A cell phone can be dangerous. It is important know what is the hazard of a cell phone. Bellow are some point to be considered for having a cell phone.

Danger from radiation

Some people have considered cell phone as dangerous item because they believe cell phone can cause cancer or tissue abnormality. This is different from what the representative of phone companies,

WHO or phone independent organization state. Those representative state that the cell phone are safe even for child.

Cell phone is new technology. There are some factor not considered yet when cell phone introduced at the first time. Here are a couple of tips you can use to improve the safety from radiation:

  • There is no scientific evidence that cell phone radiation can cause mutation to our body. But there are cases where people feel their skin got heated up when using the cell phone. Cell phone emits electromagnetic radiation. A high amount of high frequency radiation can make our body heat up.
  • Cell phone radiation shield will not protect you from radiation. On google you will find many advertisers promoting their cell phone shielding device. They are scam. Shielding will not protect you from radiation since the radiation are know to be able to pass trough wall or metal. In fact if the shielding device actually work, it will make the cell phone produce more radiation to enable it to connect to the nearest base station.
  • WHO state this on Fact Sheet 193 (revised June 2000): Scientific evidence does not indicate any need for RF-absorbing covers or other absorbing device on mobile phones. They cannot be justified on health grounds and the effectiveness of many such devices in reducing RF exposure is unproven. Wireless phones conform with strict safety guidelines required by the Federal Communications Commission and endorsed by other federal agencies responsible for protecting the nation's public health. Given compliance with these requirements, use of any of these products would not make any material difference in the safe use of the phone.
  • Maximum limit of cellular phone SAR standard is 1/50 hazard limit. At 100W/Kg cellular frequency can create tissue heating (there is no cell mutation mentioned).
  • Base station emit radiation greater than cell phone but people receive a lot less radiation since base station transmitter is located far from people.
  • Lower SAR do not means safer cell phone. It will only means that the cell phone will have more trouble connecting to the network
  • EGPRS has lower SAR Than GPRS, bellow is mentioned quote inside the SAR report of Pocket PC Phone HSTNH-H06C, FCC ID NM8HHH06C:
    EGPRS mode was not measured, because maximum averaged output power is more than 2 dB lower in EGPRS mode than in GPRS mode.
  • Using headset do not reduce radiation. SAR rating of a cell phone worn on body do not necessarily lower than cell phone use at the ear, even with original accessory.
  • Real life SAR is lower than indicated on manual book
    • Hand phone do not have high SAR level all the time, it will use power level just high enough to reach the nearest cellular network base station.
    • The mentioned SAR value on cell phone manual or FCC website corresponds to tests done at the highest possible output power. In real life, the cell phone is only using a fraction of that power. Only enough power needed to reach a base station.
    • The cell phone will reduce emition radiation automatically when at listening mode. The cell phone emition radiation will reduce even more at standby mode.
    • SAR varies with the frequency channels or trasmitting bands. The indicated SAR value corresponds to the frequency which give the maximum SAR, usually at 800/850/900. Cell phone work at different frequency than those will have lower radiation.
    • Different ways of holding the phone give different SAR. The maximum value corresponds to a holding position giving a conservative test result.
    • Real life SAR can have value as small as few percent of maximum indicated.
  • Buy hand phone with speakerphone capability if you want to avoid its radiation.
  • SAR rating can be a good guidance to select phone with good reception, it do not indicate real life radiation level.

Be carefull when using signal booster

Signal booster can increase phone signal strength greatly. It can also make the phone do not comform to FCC certification anymore, because the signal emitted by phone using signal strength device can have SAR Rating bigger than FCC safety limits.
Using a passive signal booster (the one without electronics) is considerably safe, because it works just like extendable antenna do, and the phone it self still have control over signal gain strength. When using active signal booster, the phone do not have control on how much power to emit in order to reach the network adequately. When the signal booster emit the signal too strong the phone will emit greater radiation than standard, also this will hampering cellular network, making other user hard to connect to network.

Do not use your cell phone inside your car

There are a couple of reason for this:

  • Danger of radiation. When used in isolated environment, phone will have difficulty in reaching the network, so it will increase the power level to reach it. Your phone will have power level higher inside the car than outside. If you care about phone radiation do not use it inside a car or isolated metal area (plane, ship). Car metal body create faraday effect. The metal make radiation bounce back inside, this will accumulate the radiation power.
  • Greater risk of accident. Cell phone are know to make the driver distracted. There are cases where the accident happen while driver having a conversation trough a cell phone. Some contry already made cell phone use while driving illegal because of this.

Do not use fake batteries or charger

Fake battery or charger can introduce hazard to your cell phone. Especially if the battery is lithium based type. Lithium based battery are easier to explode. Dent and heat can cause explosion. For safety precaution, do not place the battery close to you while charging. Do this too for about one hour after charging. Fake lithium battery is dangerous since the poor quality make them more prone to problem, espcially if it's Li Polymer.

Do not use your phone at gas station or hospital

  • Most people consider the use of cell phone in gas station is safe, but the use of cell phone near gas station may interfere the operation of gas station billing system. Some people also argue that cell phone may produce internal spark and can ignite the fuel vapor usually produced while filling the vehicle fuel. If you must use your cell phone in a gas station, do not use it near the filling station.
  • Don't use your handphone near a pacemaker device. Pacemaker device is a sensitive device. Cell phone emit radiation that is big enough to cause interference to pace maker device. Cell phone also interfere the operation of sensitive device in a hospital. It is best to deactivate your phone if you go near an operating room or near a sensitive device.
(Source from: http://www.cellphonespec.com/content/handphone-safety-and-health-guide)