Limits of Human Exposure to Radiofrequency Electromagnetic Fields in the Frequency Range from 3 KHZ to 300 GHZ - Safety Code 6

6. RF Surveys

6.1 RF Survey Procedures The objective of a survey is to determine whether the device or installation complies with recommended standards of performance and personnel exposure, and to assess the effect of the location of the device with respect to controlled and uncontrolled areas in the environment. The following recommendations are made with respect to RF surveys:

1. RF surveys shall be carried out by competent persons.
2. Before routine operations begin, an RF survey shall be conducted for all new installations capable of producing levels exceeding those specified in Section 2.2.
3. A survey shall be made following any repairs, increases in radiated power or changes in working conditions, protective shielding and barriers that may increase the levels, to ensure that the levels do not exceed the limits specified in Section 2. This refers both to RF and microwave exposed workers and the general public.
4. A survey shall be conducted when any malfunction that may increase the field levels, induced body currents or contact currents is suspected.
5. A survey shall be conducted as frequently as practically possible around devices and at installations which are capable of producing fields, induced body currents or contact currents in excess of the limits set out in Section 2.
6. Survey instruments shall be selected to match the RF source and exposure conditions such as frequency, level of field strength or power density, near- or far-field. It is suggested that the measurement techniques specified in Appendix V be followed. Alternatively, other suitable techniques may be used(15,16). Survey instruments shall be fully calibrated at least once every three years. Their performance should be checked against another calibrated instrument before carrying out a survey.
7. During a survey, a complete record of the field parameters (electric field strength, magnetic field strength or power density and induced body and contact currents) at each work site shall be kept to assist in making a realistic evaluation of compliance.
8. During the inspection of any RF device or installation, all safety interlocks and "ON-OFF" control switches shall be examined and placed in working order. The required warning signs, labels and tags must be readable and properly affixed to the device.

6.2 Records and Recommendations

1. Records shall be kept of all RF survey measurements and their evaluation. The records shall include the date the measurements were made, number and type of devices in the area surveyed, the locations of measurement with respect to the RF emitting device, names and organization of who conducted the survey, survey results, as well as the model, serial number and calibration date of the measuring instrument(s) used. Other information that may prove useful would be photographs, floor plans, etc.
2. Recommendations on appropriate changes in shielding, location and operation of the device, based on the evaluation of the survey measurements, shall be made to the person(s) responsible for the device. When a remedial action based on these recommendations has been taken, another survey should be made to verify the effectiveness of the actions.