True anomaly

Specific absorption rate (SAR) is a measure of the rate at which energy is absorbed by the human body when exposed to a radio frequency (RF) electromagnetic field; although, it can also refer to absorption of other forms of energy by tissue, including ultrasound. It is defined as the power absorbed per mass of tissue and has units of watts per kilogram (W/kg).

SAR is usually averaged either over the whole body, or over a small sample volume (typically 1 g or 10 g of tissue). The value cited is then the maximum level measured in the body part studied over the stated volume or mass.

Calculation

SAR for electromagnetic energy can be calculated from the electric field within the tissue as:

$\text{SAR}=\underset{\text{<mrow data-mjx-texclass="ORD">sample</mrow>}}{\int }\frac{\sigma (\mathbf{r})|\mathbf{E}(\mathbf{r}){|}^2}{\rho (\mathbf{r})}d\mathbf{r}$

where

$\sigma$ is the sample electrical conductivity

$E$ is the RMS electric field

$\rho$ is the sample density

SAR measures exposure to fields between 100 kHz and 10 GHz (generally known as radio waves). It is commonly used to measure power absorbed from mobile phones and during MRI scans. The value will depend heavily on the geometry of the part of the body that is exposed to the RF energy, and on the exact location and geometry of the RF source. Thus tests must be made with each specific source, such as a mobile phone model, and at the intended position of use.

Mobile phone SAR testing

DTZ's public sale group in Singapore auctions all forms of residential, workplace and retail properties, outlets, homes, lodges, boarding homes, industrial buildings and development websites. Auctions are at present held as soon as a month.

We will not only get you a property at a rock-backside price but also in an space that you've got longed for. You simply must chill out back after giving us the accountability. We will assure you 100% satisfaction. Since we now have been working in the Singapore actual property market for a very long time, we know the place you may get the best property at the right price. You will also be extremely benefited by choosing us, as we may even let you know about the precise time to invest in the Singapore actual property market.

The Hexacube is offering new ec launch singapore business property for sale Singapore investors want to contemplate. Residents of the realm will likely appreciate that they'll customize the business area that they wish to purchase as properly. This venture represents one of the crucial expansive buildings offered in Singapore up to now. Many investors will possible want to try how they will customise the property that they do determine to buy by means of here. This location has offered folks the prospect that they should understand extra about how this course of can work as well.

Singapore has been beckoning to traders ever since the value of properties in Singapore started sky rocketing just a few years again. Many businesses have their places of work in Singapore and prefer to own their own workplace area within the country once they decide to have a everlasting office. Rentals in Singapore in the corporate sector can make sense for some time until a business has discovered a agency footing. Finding Commercial Property Singapore takes a variety of time and effort but might be very rewarding in the long term.

is changing into a rising pattern among Singaporeans as the standard of living is increasing over time and more Singaporeans have abundance of capital to invest on properties. Investing in the personal properties in Singapore I would like to applaud you for arising with such a book which covers the secrets and techniques and tips of among the profitable Singapore property buyers. I believe many novice investors will profit quite a bit from studying and making use of some of the tips shared by the gurus." – Woo Chee Hoe Special bonus for consumers of Secrets of Singapore Property Gurus Actually, I can't consider one other resource on the market that teaches you all the points above about Singapore property at such a low value. Can you? Condominium For Sale (D09) – Yong An Park For Lease

In 12 months 2013, c ommercial retails, shoebox residences and mass market properties continued to be the celebrities of the property market. Models are snapped up in report time and at document breaking prices. Builders are having fun with overwhelming demand and patrons need more. We feel that these segments of the property market are booming is a repercussion of the property cooling measures no.6 and no. 7. With additional buyer's stamp responsibility imposed on residential properties, buyers change their focus to commercial and industrial properties. I imagine every property purchasers need their property funding to understand in value. When measuring the SAR due to a mobile phone the phone is placed at the head in a talk position. The SAR value is then measured at the location that has the highest absorption rate in the entire head, which in the case of a mobile phone is often as close to the phone's antenna as possible. Various governments have defined maximum SAR levels for RF energy emitted by mobile devices:

• United States: the FCC requires that phones sold have a SAR level at or below 1.6 watts per kilogram (W/kg) taken over the volume containing a mass of 1 gram of tissue that is absorbing the most signal.
• European Union: CENELEC specify SAR limits within the EU, following IEC standards. For mobile phones, and other such hand-held devices, the SAR limit is 2 W/kg averaged over the 10 g of tissue absorbing the most signal (IEC 62209-1).
• India: switched from the EU limits to the US limits for mobile handsets in 2012. Unlike the US, India will not rely solely on SAR measurements provided by manufacturers; random compliance tests are done by a government-run Telecom Engineering Centre (TEC) SAR Laboratory on handsets and 10% of towers. All handsets must have a hand free mode.

SAR values are heavily dependent on the size of the averaging volume. Without information about the averaging volume used, comparisons between different measurements cannot be made. Thus, the European 10-gram ratings should be compared among themselves, and the American 1-gram ratings should only be compared among themselves.

MRI scanner SAR testing

For Magnetic Resonance Imaging the limits (described in IEC 60601-2-33) are slightly more complicated:

	Whole body SAR	Partial body SAR	Head SAR	Local SAR (a)
Body Region →	whole body	exposed body part	head	head	trunk	extremities
Operating Mode ↓	(W/kg)	(W/kg)	(W/kg)	(W/kg)	(W/kg)	(W/kg)
Normal	2	2 - 10 (b)	3.2	10 (c)	10	20
1st Level Controlled	4	4 - 10 (b)	3.2	20 (c)	20	40
2nd Level Controlled	>4	>(4 - 10) (b)	>3.2	>20 (c)	>20	>40
Short duration SAR	The SAR limit over any 10 s period shall not exceed two times the stated values

Note: Averaging time of 6 minutes.

(a) Local SAR is determined over the mass of 10 g.

(b) The limit scales dynamically with the ratio "exposed patient mass / patient mass":

NORMAL OPERATING MODE: Partial body SAR = 10 W/kg – (8 W/kg * exposed patient mass / patient mass)
FIRST LEVEL CONTROLLED OPERATING MODE: Partial body SAR = 10 W/kg – (6 W/kg * exposed patient mass / patient mass)

(c) In cases where the orbit is in the field of a small local RF transmit coil, care should be taken to ensure that the temperature rise is limited to 1 °C.

Criticism

SAR limits set by law don't consider that the human body is particularly sensitive to the power peaks or frequencies responsible for the microwave hearing effect. Frey reports that the microwave hearing effect occurs with average power density exposures of 400 μw/cm², well below SAR limits (as set by government regulations).

Notes:

In comparison to the short term, relatively intensive exposures described above, for long term environmental exposure of the general public there is a limit of 0.08 W/kg averaged over the whole body. A whole-body average SAR of 0.4 W/kg has therefore been chosen as the restriction that provides adequate protection for occupational exposure. An additional safety factor of 5 is introduced for exposure of the public, giving an average whole-body SAR limit of 0.08 W/kg.

FCC advice

The FCC Guide, "Specific Absorption Rate (SAR) For Cell Phones: What It Means For You," after detailing the limitations of SAR values, offers the following "bottom line" editorial:

31 year-old Systems Analyst Bud from Deep River, spends time with pursuits for instance r/c cars, property developers new condo in singapore singapore and books. Last month just traveled to Orkhon Valley Cultural Landscape.

See also

• Comparison of specific absorption rate for devices
• Dielectric heating
• Electromagnetic radiation and health

References

43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.

External links

• Radiation in Mobile Phones: An Analysis antenna-theory.com
• FCC: Cellular Telephone Specific Absorption Rate
• World Health Organization: Electromagnetic fields and public health
• Cell Phone Radiation Levels, CNET article and comprehensive listings
• An Update on SAR Standards and the Basic Requirements for SAR Assessment
• Motorola's SAR Website
• Nokia's SAR Website
• Samsung mobile's SAR website
• Sony Ericsson's SAR Website
• SAR of some mobile phones
• Example of a detailed SAR report on the FCC web site (for an Apple iPod Touch 4G)