General Policing Issues
mmO2
Airwave TETRA Radio System
The
Scottish Police Federation (and others) asks whether HSE has any health
concerns with the Airwave radio network being rolled out to Police
Forces in the UK , and can give assurances that it is safe.
Introduction:
The
questions are not easy to answer to everyone's satisfaction, as it
is not possible to prove a negative. HSE can't state categorically
that exposure to emissions from electromagnetic fields in general,
or TETRA specifically, is safe. However, a number of useful things
can be done that include assessments of any risks, reviewing relevant
data and information, and evaluating research findings. When this
approach is applied, it can form the basis by which conclusions may
be drawn about risks to health and safety.
Background:
There
are two key components to the Airwave network:
•
The infrastructure, comprising a series of base stations providing
radio coverage over the majority of the country.
•
The terminal equipment, which may be either vehicle mounted
or hand held two-way radios.
The
Home Office have contracted Airwave to provide the infrastructure,
but individual Police Forces source the terminal equipment used by
their officers from any of a number of manufacturers (e.g., Sepura,
Motorola, Nokia etc). Purchasing advice is provided to Forces by the
Police Information Technology Organisation (PITO).
Legislation
and Standards:
The
HSE view stems from consideration of the duties of employers to provide
a place of work for their employees that is safe and without risks
to health as set out in the Health and Safety at Work Act, 1974 (HASAWA74).
Included within the general duties is the requirement that articles
and substances provided for use at work are also safe and without
risks to health. For equipment that emits electromagnetic radiation,
such as TETRA radios, there are no emission limits specified.
The
European Communities for electrotechnical standardisation (CENELEC)
are developing a series of specifications for assessing the emissions
from mobile phones and similar transmitting devices. The assessments
compare potential exposures of users with the numerical guidelines
recommended by the International Commission for Non-Ionizing Radiations
(ICNIRP, 1998). One set of standards was mandated for consumer goods
and refers to the guidelines for members of the public as expressed
in the European Council Recommendation EC/519/1999. The European Commission
has recently issued a mandate to CENELEC to provide technical specifications
for how employers may undertake the risk assessments required by Article
4 of the European Council Directive EC/40/2004. Until these standards
are all in place, Me mber States may use national standards and guidance.
In the UK , the National Radiological Protection Board (NRPB) has
provided that guidance in their publication, "“Advice on Limiting
Exposure to Electromagnetic Fields” (NRPB04). This advice recommends
the adoption of the ICNIRP 1998 Guidelines (which also form the numerical
basis for Directive 2004/40/EC).
The
recommendations of both NRPB and ICNIRP are designed to prevent the
acute effects of exposure to EMFs. Both organisations also concluded
that the results of studies investigating suggested long-term effects
are insufficient to form the basis for exposure restrictions.
The
ICNIRP Guidelines establish basic restrictions in (EC/40/2004, these
are called exposure limit values that are not to be exceeded) to assure
the safety of people exposed to electromagnetic fields. For the emissions
from TETRA radios (operating at around 400 MHz) these are expressed
in terms of the specific energy absorption rates (SAR) in the body
(or parts of it). Basic restriction, SAR, values for workers have
been established at approximately one tenth of the level at which
acute effects are first observed. As the general public include a
wider variety of people, some of who will have varying susceptibility
to the effects of heating (e.g., infants, the infirm or the very old),
a further reduction factor of 5 is applied to obtain the relevant
basic restrictions that are specified in EC/519/1999.
In
practice, the manufacturers of the terminal equipment design and build
their equipment so that it will not expose users to SAR levels that
would exceed those incorporated in the European Recommendation for
restricting exposures of members of the public to EMFs (EC/519/1999).
Even
if a number of officers were to operate their radios together in close
proximity, the contribution to an individual's exposure by the emissions
from their colleagues' radios is going to be a fraction of a percent
of that which they receive from their own radio. This is due to the
significantly greater distance between the antennae of the transmitters
and the other officers.
Summary
& Conclusions:
HSE
believes that the use of the Airwave TETRA radio network by Police
Officers will comply with the requirements of the Health and Safety
at Work, etc Act, 1974, provided that it is used in accordance with
the manufacturers' instructions.
The
European Directive, EC/40/2004, will be transposed into UK national
legislation by April 2008.
HSE
is pleased that the Home Office has chosen to fund a large programme
of research into the interaction of TETRA signals with people, some
of which is being conducted within the LINK MTHR Programme http://www.
m thr.org.uk/ Results of the HO funded work can be found at this
website:
http://www.policereform.go
v .u k /implem e ntation/tet r a/ind e x.html
HSE
will continue to review the results of research and participate in
international programmes, to study the effects of EMFs on the health
of people, such as those organised by the World Health Organisation
( http://www.who . int/peh-emf
).
References:
HASAWA74
The Health and Safety at Work,
etc, Act 1974
ICNIRP98
Guidelines for limiting exposure to time-varying
electric, magnetic and electromagnetic fields (up to 300 GHz); http://www.icn
i rp.org/
EC/519/1999
Council Recommendation of 12 July 1999 on
the limitation of exposure of the general public to EMFs (0 Hz to
300 GHz);
