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Occupational and general public exposure due to very high frequency (VHF)/ultra high frequency (UHF) transmission centres for verbal communication for air traffic control is investigated in situ for the first time. These systems are used for communication with aircraft, resulting in different human exposure from that of classical broadcasting. Measurement methods are proposed for the exposure assessment, and a measurement campaign is executed in three transmission centres. By investigating the temporal behaviour of the VHF signals for 6 d, a realistic worst-case duty cycle of 29 % is determined. Periods of high exposures corresponding with high aircraft traffic are from 7 a.m. to 1 p.m. and in the evening. All measured electric-field values satisfy the International Commission on Non-ionizing Radiation Protection guidelines. Fields vary from 0.2 to 21.1 V m–1 for occupational exposure and from 0.007 to 8.0 V m–1 for general public exposure. The average fields equal 5.2 V m–1 for workers, and 0.7 V m–1 for general public. [ABSTRACT FROM AUTHOR]

Electromagnetic radiation of electronic article surveillance (EAS) systems was investigated in situ for both the detection gate panels and the activators and deactivators. ‘Safety distances’ for the general public, defined as the distances outside which the magnetic field levels of the EAS systems do not exceed the The International Commission on Non-ionising Radiation Protection reference levels, were determined. Additionally, temporal and frequency behaviour, and signal waveforms were investigated. For the detection gates, the spatially averaged fields exceeded the reference levels for five of the six investigated systems. For the (de)activators, the spatially averaged fields did not exceed the reference levels. Maximal fields up to 148.0 A m−1 were measured from 20 cm on. The exposure ratios varied from 8 to 13 for EM, from 6 to 8 for AM and from 0.008 to 1.8 for RF systems. Safety distances were maximally 111 cm for EM, 77 cm for AM and 35 cm for RF systems. [ABSTRACT FROM PUBLISHER]