Real danger of going radio gaga? - Communications

Following the health scare on the radiation risk from mobile phones, digital radio comes under scrutiny as the next big threat. The Home Office has just published interim research into the health risks associated with digital radio, and announced funding for further research. But what is the real story? What are the health and safety issues? Should firefighters be worried that as they overcome the dangers of the fireground, might it be their radio that harms them?

The Fire Service needs a better, more sophisticated communications system. There is no doubt about it that current analogue radios are wholly inadequate. TETRA and Tetrapol offer more modern capabilities designed to make a firefighter's job easier and in many respects safer. Recent press reports, however, effusively question that last point, to the degree that many in the emergency services are beginning to wonder if modern communications systems might add to the dangers of the job.

Since health concerns over GSM mobile phones first came to light, scientists have called for further research and the Home Office has just announced plans to carry it out. In the meantime, Airwave (based on TETRA) continues to be rolled out to police forces around the UK and the two giants of digital PMR technology battle it out to win the national contract for the Fire Service.

THE HEALTH RISK

The main bone of contention is that these two systems are based on high frequency, non-ionising microwave radiation technologies (just like GSM). There are experts who are seriously worried that long-term use of the radios could be detrimental to health and they say they have evidence to support their concerns. There are others who say that certain individuals may be more susceptible to microwave radiation--just as some people are allergic to peanuts and others are not--and that their "allergy" may not become apparent until potentially serious side-effects are felt. There are compelling arguments for and against the health aspects of these systems but no one, as yet, knows for certain either way.

THE BRAIN FUNCTION EFFECT

TETRA is an open European standard developed from within and ratified by ETSI (European Telecommunications Standards Institute). As such there are a number of companies supporting and manufacturing TETRA equipment. It is a four slot (four channels per 25KHz) TDMA technology, which makes it ideally suited for applications of high-traffic volume.

However, the recent Stewart Report into the health and safety of mobile phones advises against the use of mobile or wireless RF devices that pulse at or near 16Hz as they could interfere with brain activity. TETRA base frame rate pulses at 17.6Hz from the handset, placing it dangerously close to that frequency. A Professor Salford at Lund University in Sweden has discovered that pulsing at 16Hz can alter the permeability of the blood-brain barrier in Rats. If occurring m humans, he says, this could have a profound effect on brain function.

Specifically the warning centres on a potential breakdown in the brain's capacity to generate calcium, which is needed for many biological functions in the body.

This warning has been acknowledged and is echoed by the statutory advisory body to the Government, the NRPB, in its report into the possible health effects from TETRA. It says: 'There is no epidemiological evidence specifically concerned with exposure to TETRA signals, or to RF radiation modulated at around 16Hz ... However, they do not exclude the possibility of a risk of cancer that appears only after many years of exposure, nor of a hazard from RF radiation modulated specifically at around 16Hz'.

THE MICROWAVE RADIATION THREAT

Tetrapol has been around longer than TETRA and for this reason some would argue it is more stable and mature. It is almost (but not quite) an open standard, conforming to most of the standardisation ratified by ETSI (and recognised as one by the ITU). it was made into a PAS (Publicly Available Specification) in the late 1980s. Whereas it has many more implementations around the world than TETRA, there are fewer manufacturers designing equipment for use on the system. Tetrapol's background technology is FDMA, which is not pulsed. It is, however, still a non-ionising radiation technology and as such is not completely without implication.

There are other significant differences between the two technologies. Tetrapol's advantage is mast ratio. Fewer radio masts are needed to cover the same area as TETRA. As far as health and safety is concerned, pressure groups are worried about base stations, masts, antennas and radios. Franz Niederer, President of the Tetrapol Users' Club, says: "In cities you have to add more base stations to increase signal strength. But Tetrapol still requires fewer masts than TETRA. In Berlin, for example, we only have six base stations to cover the whole city."

Airwave is planning to erect around 3,500 radio masts to cover 100 per cent of the UK, a project that is already 60-70 per cent complete. In the South West region of England and Wales, Tetrapol claims to have built or is planning to build only 57 radio masts; Airwave requires around 260 to cover the same area.

As far as radios are concerned the primary health and safety concern is around the emission of microwave radiation directly into the brain. TETRA, Tetrapol and GSM mobile phones could all potentially do this. TETRA is pulsed, which means there is a further risk, but other issues are the likelihood that the radios might affect other equipment, such as in hospitals or even in-cab computers.

THE ONE NETWORK FLAW

Another serious safety issue, which experts caution against since 9/11, could come to light if the Government chooses 02 Airwave as the network for the Fire Service when the successful bidder is announced in 2004. This will mean both Police and the Fire Service will operate on the same national network. Graham Wilde, chief author of the BWCS (an independent wireless consultancy) report of 2002 warns that reliance on a single network will put firefighters and police officers in serious danger. If one goes down or gets ousted (as happened in New York) there is no back up.

At the end of May, the Home Office made the controversial announcement that it is to spend 5 million [pounds sterling] on a health monitoring study to help ensure the safety of Airwave. Imperial College, London, will monitor more than 100,000 police officers for any impact on health for the next 15 years. The announcement as made in response to calls for further research by independent scientists and leading experts. Rather than assuaging public opinion, however, it has caused outrage among police officers using the new system, many of whom feel they are being used as guinea pigs.

The Home Office argues: "We've been doing research into this for a while but in order to do full-scale user research such as this you need enough users," said a spokesperson.

Richard Bond from Motorola comments: "We're supportive of the Government's plans to conduct this research and confident that no problems will be found."

THE AGE OF ANXIETY

At present, most TETRA and Tetrapol networks are used purely for voice communication but both technologies support data transmission. For the Fire Service this will enable commanders and fire officers at the fireground to receive information such as area maps, building plans, information about dangerous substances and so on. It will also enable them to send and receive video images. To do this requires that the system use more than one time slot. This could increase the pulse frequency, which would require an increase in power. Unless the design and position of the hand portable or radio changes the average radiation exposure to the user will be increased, warn the experts.

NRPB says: "The TETRA system will cause people's exposure to RF fields to be increased in a number of different ways but to a smaller extent than the same usage of the present analogue systems that they are designed to replace." However, what they do not make clear is that the frequency at which both TETRA and Tetrapol operate (380-420MHz for TETRA, 380-512MHz for Tetrapol in the UK) is classed as microwave not radio wave as with the lower frequencies of VHF analogue networks (140-150MHz). Some scientists point out that microwave radiation is more harmful

Barrie Trower, a scientist with experience working for the Ministry of Defence, has grave concerns: "Microwaves have been used as stealth weapons in the past. They can be used safely by having transmitters away from populated areas but you would have to turn up the power and it would be more expensive to do this."

He is particularly concerned by the use of radiation emitting radio equipment in cars or fire engine cabs: "This is even worse because the waves will bounce around inside the vehicle in effect turning it into a microwave oven."

Dr Mike Clark, spokesman for the NRPB said: "Because of BSE and such like, this is the age of anxiety. No actual link between radio waves and cancer has been proved but if fire officers are worried they should ask for hands-flee kits." He then went on to say: "It is generally true that some people may be more susceptible to radiation than others. The main hypothesis is that these phones could affect thought patterns in certain ways but this won't become apparent for another 30 years or so."

THE MAVERICK BRIGADE

Shropshire Fire and Rescue Service's decision to go against requests from the Government to sign up to the national procurement process for a replacement wide area radio system has come in for criticism. The authority has signed up to O2 Airwave to the annoyance and anger of senior Government figures. In the event that a different network (such as Tetrapol) is chosen, this could seriously disrupt plans for interoperability between the emergency services, they say.

Steve Worrell, Programme Manager at Shropshire, defended his decision by saying: "We had valid and compelling reasons for doing this now. This is an interim solution procured on a five-year lease basis. It will integrate with the solution offered by Firelink as and when that's ready."

It seems no one really knows for sure whether there will be any long-term effects from using these systems. And it is fair to say that everyone who we talked to who is using either system is emphatic about the features and benefits. Undermining any attempt to modernise communications in the Fire Service will be far more dangerous to the health of fire officers in the short and long term.

It seems that, as with mobile phones, once they start using it and realise the benefits their worries over health concerns dramatically decrease (or disappear). However, there is compelling evidence to suggest that more extensive research (such as the Home Office has announced) is needed.

The key issue is that users should be made fully aware of what the perceived and unknown dangers are or may be and allowed to choose what precautions they take to avoid or lessen them. This is about choice. Firefighting is a dangerous occupation, as is policing. Firefighters want to be aware of the dangers so that they can make informed decisions as to how to handle them.

The views in this report are the authors and do not necessarily reflect FIRE's own

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