NIOSH evaluated radiofrequency electric and magnetic field exposures at an atomic time radio station in Hawaii as part of the agency's Health Hazard Evaluation (HHE) Program. NIOSH investigators visited the radio station in January 2012 in response to a request from health and safety managers who were concerned about possible radiofrequency exposures at the station, which broadcasts time announcements, standard time intervals, standard frequencies, geophysical alerts, marine storm warnings, and global positioning system status reports. Most of the antennas at the facility were located in the antenna field, the area between the radio station building and the beach.
NIOSH investigators found that while electric and magnetic field strengths exceeded action levels and occupational exposure limits (OELs) in certain areas near the station’s antennas, the field strengths measured on the roof, in the office, and in the transmission room of the building were below action levels and OELs. The agency’s report concludes that even though employees spent little time in the antenna field, they could be overexposed to magnetic fields from nearby transmitting antennas while working on antennas that are powered off, or when servicing the facility’s nearby weather station.
Based on their findings, NIOSH investigators provided several recommendations to reduce exposures at the radio station, including:
develop a comprehensive radiofrequency safety program
maintain an inventory of radiofrequency sources that have the potential to produce electric and magnetic field strengths near or above action levels or OELs
provide annual radiofrequency safety awareness training
modify the incident reporting system to include possible radiofrequency overexposure incidents
For more information, view the HHE report, which was released last week. Other NIOSH HHE reports are available on the agency’s website.