The first phase of a project to find out if mobile phone masts damage our health is being launched this week, by Essex University researchers.
Potential risk to health is of concern to people up and down the country
As part of the study, questionnaires are being sent out to 20,000 homes in and around Colchester - including Chelmsford, Ipswich and Braintree.
The research team was awarded £250,000 to look at widespread public concern about the masts.
The first phase will look at people's sensitivity to the masts.
The study, lead by the psychology department, will also look at what forms this sensitivity occurs.
Professor Elaine Fox, who is leading the project, said: "We need as many members of the public as possible to complete and return their questionnaires.
"This survey, and the results we hope to achieve from it, will be instrumental in finding out just how many people experience symptoms associated with electromagnetic hypersensitivity syndrome (EHS) and in creating a index that can easily identify sensitive individuals."
The team aim to analyse the responses from the questionnaires over the next few months.
The next stage of the project will then be to invite people to participate in a study to determine whether exposure to electromagnetic fields has a clear effect on their health.