Wireless Safety
March
2007
Whitepaper
DECT™ & Bluetooth® Safety Overview
DECT and Bluetooth are both short-range radio technology which transmit at a much lower output power than a
typical mobile phone. According to current scientific knowledge, there are no known health risks associated with
DECT or Bluetooth headsets and the power they transmit falls well below permissible safety limits.
Transmit Output Power
A typical 900MHz GSM mobile phone has an average power of up to
250mW
.
An typical DECT telephony handset Transmit power is much less at just
10.43mW
(250mW x (417us /10000us))
whilst a Plantronics DECT headset Transmit power is typically a mere
0.26mW
(6.3mW x (417us /10000us).
Bluetooth headsets transmit at even lower levels, given a range of 10m versus up to 100m for DECT.
Put another way, Plantronics DECT and Bluetooth headsets output about 0.1% of the transmit power of a
typical mobile phone and 2.5% of the power of a typical DECT handset.
Safety Limits and SAR
For radio devices it has become standard to measure the Specific Absorption Rate (SAR) of the product. SAR testing
is an effective method of quantifying the amount of energy absorbed into biological tissue, particularly the human
body.
The majority of SAR testing is focused on the head where the current limits for uncontrolled exposure are
2W/kg
for
10g Volume Averaged SAR for Europe, Japan and Korea.
A SAR value is not usually specified for DECT or Bluetooth headsets as the transmit power is so low as to guarantee
a SAR value well below the basic test limits. As such, these headsets meet the exclusion conditions of the European
Standards for this type of testing, such as ES 59005 and EN50360/EN50361.
Although there is no requirement to do so, Plantronics has commissioned independent testing, with results clearly
showing that the SAR levels are far below those required to comply with international standards:
•
SAR for a mobile phone: typically
0.3 to 1.5 W/kg
for 10g Volume Averaged
•
SAR for a Plantronics CS60 DECT headset:
0.0006 W/kg
for 10g Volume Averaged
•
SAR for a Plantronics
M3000 Bluetooth headset
– 0.03 W/kg
for 10g Volume Averaged
The above figures show that a typical Plantronics Bluetooth or DECT
headset operates at in the range of just
0.03% to 1.5% of the recommended European SAR limit. Considering typical mobiles phones operate in the
range between 15% and 75% of the SAR limit, it can clearly be seen that headsets are very low powered.
