Background A Job-Exposure-Matrix (JEM) for occupational exposure to radiofrequency (RF) electromagnetic field (EMF) was previously developed based on source measurements and not on personal measurement data. In the framework of an international study aimed at validating and enriching the JEM, we conducted a pilot study of personal measurements of occupational exposure to RF fields in a rehabilitation department of a Spanish hospital among various groups of workers in order to develop a protocol for the main field study in three countries.

Methods We previously identified and prioritized the types of occupations to be measured based on their presumed levels of exposure to RF fields from the RF-JEM and based on expert judgment. A screening questionnaire was used to identify potential participants, based on their job titles and reported sources of RF exposure. Consequently, personal full-shift measurements were collected. In addition, a worker’s dairy collecting information on occupational-specific sources of RF used during the measurement day, the use of personal mobile phones and general occupational data was filled in by every participant at the end of the shift.

Results A total of 16 workers (cleaning staff, receptionists and physiotherapists) participated in the Spanish pilot test. Overall geometric and arithmetic personal exposure levels were low; however, peaks of exposure to electric (>125 V/m) and magnetic fields (>0,55 A/m) exceeding the ICNIRP 1998 occupational standards at the frequency of 27,12 MHz were observed for a small number of participants, though peak duration was brief and their frequency scarce.

Conclusion We performed personal measurements of RF occupational exposure in a pilot study within the framework of an international study. Measurements will be performed across a wide range of occupations in Spain, France and the Netherlands and will be used to update and enhance an existing RF-JEM to be use in occupational epidemiological research.