There is no evidence of an increased risk of cancer for people living near the RAF Fylingdales radar base in North Yorkshire, according to a report.
RAF Fylingdales will soon be upgraded with new technology
The Scarborough, Whitby and Ryedale primary care trust (PCT) study found no difference between cancer rates in villages around the site and the wider area.
But it recommends further monitoring of the early warning base and says long-term research is needed to discount any possible link to human health problems.
Critics of RAF Fylingdales welcomed the conclusion but said the report only scratched the surface of the issue.
They argue that it will be a number of years before the health effects of low radio frequency radiation from the base showed up in statistics after its last technology upgrade in the late 1980s.
The PCT launched the study in response to a BBC documentary which reported possible cancer clusters near a similar early warning base at Cape Cod in the US.
Dr Jeffrie Strang, the PCT's Director of Public Health, told BBC News Online that local people should be reassured by his findings.
"What we have done in the look back exercise shows that Fylingdales is as safe - if not safer - than the primary care trust area as a whole," he said.
"I am pleased to be able to say that this retrospective study does not provide evidence of a link between RAF Fylingdales and cancer registrations.
"We do take it seriously because it's important to people in the area and we feel we can totally reassure the population they are safe."
Dr Strang looked at cancer registrations in the wards of Derwent, Ebberston, Eskdaleside, Fylingdales, Pickering and Thornton-le-Dale between 1991 and 1999.
Figures showed that rates were either statistically lower or similar to Scarborough and the PCT as a whole during the period after the last technology upgrade at the RAF base.
While the report recommends long-term research, Dr Strang has doubts as to whether this is feasible because of emissions from other sources such as mobile phones, televisions and computers.
He argued: "The best way forward is to carry on monitoring the cancer rates to reassure the population around Fylingdales.
"There is a wealth of epidemiological studies into low level frequency radiation and no-one has come up with any substantive evidence of a link to cancer."
But campaign group Fylingdales Action Network said this was exactly the kind of study that should be carried out at the base.
Spokesman Keith Morrison said: "There should be continuous monitoring of radiation at agreed points so we know what is coming out and when.
"The real problem is not RAF Fylingdales during its total time, but with the radar that has only been in ten years.
"Research shows that this radiation takes a period of time for these health effects to show up."
"We have talked to people who have done work on electromagnetic radiation and although in theory they can see the various ways it can effect humans, they are not entirely sure how it manifests itself."
Yorkshire CND also expressed reservations about the scope of the PCT's report.
Its development worker, Neil Kingsnorth, welcomed the study but said it should be just the first step to a further investigation.
"Fylingdales poses a potential threat to health through the rare type of pulsed radiation and through the long-term effects of the radar's beam," he said.
"The government has a responsibility to fully investigate the whole spectrum of potential health effects of his type of radar. This report has not done that."
Work will shortly begin on another technology upgrade at the base to bring it into line with the US missile defence programme, dubbed "Son of Star Wars".
An MoD spokesman said: "The Ministry of Defence welcomes the results of the study, which found that there was no significant difference between the rates of cancer in the areas around RAF Fylingdales and the rates in either the Primary Care Trust catchment area or in the Northern and Yorkshire region including South Humber.
"The study does not provide evidence of a link between RAF Fylingdales and cancer registrations.
"The MoD will co-operate with the Primary Care Trust in seeking to establish the feasibility of any further study."