Electromagnetic Field Exposure

Strong electromagnetic signals harm human health.

Equipment like radio transmitter or associated products must be handled with consideration of exposure to radio electromagnetic fields (electromagnetic radiation).
Working with high-voltage equipment or facilities risks exposure to high-frequency electromagnetic fields.
Radio service carriers and other users must comply with local laws and regulations when deploying wireless base station transceivers, or other equipment or facilities.
Re-evaluate the risk of electromagnetic field exposure prior to equipment structure or antenna modification.
Re-evaluate the risk of electromagnetic field exposure prior to modification of radio frequency (RF) output specifications or parameters.
Re-evaluate the risk of electromagnetic field exposure prior to modification of the site environment where equipment or facilities are located.

Restricted Areas

An area with excessive electromagnetic field exposure is considered hazardous and must be at a specified distance away from the equipment or facility as stipulated by related exposure control limits. This distance controls exposure to the electromagnetic field by personnel or the public. Maintain this distance with measures including but not limited to:

Plan to situate the equipment or facility in an area inaccessible and undisclosed to the public.
Allow only authorized and trained personnel to access the site.
Before entering the restricted area, personnel should be aware that it is restricted and shut down the transmitter.
Set clear signs at the site to remind personnel that the area is restricted.
Conduct regular post-installation monitoring and checks.
Set effective physical shields and warning signs in all areas with excessive electromagnetic field exposure.
Install an isolating device around the equipment structure.
Comply with local regulations during operation.

Installation and Usage of a Wireless Base Station Transceiver

A base transceiver station (BTS) is designed to emit less RF electromagnetic radiation than the maximum standard hazardous limit. A normal working BTS is therefore not harmful to the public and operating personnel. Defective antenna cables or other defects may however result in the emission of excessive RF electromagnetic radiation.

Personnel must abide by the following rules during BTS installation and operation:

Read through all safety recommendations and comply with local regulations before proceeding.
Before installing or maintaining an antenna close to the tower or mast with a BTS and its antenna, contact related personnel to switch off the antenna transmitter.
Personnel at the site should carry a radiation monitoring and alarm instrument.

To shield the public from electromagnetic field exposure, abide by the following guiding principles during BTS antenna site installation:

Install rooftop antennas out of reach of human activity.
Install rooftop transmission antennas away from areas with high traffic, such as the rooftop access point, telephony service point, and HVAC equipment.
Install rooftop directional antennas on the periphery and facing away from buildings.
Choose the most suitable antenna size by balancing better signal coverage with less visual impact.
Install antennas as far away as possible without compromising local area requirements.
Exercise caution when constructing a common installation site for antennas from different manufacturers, especially high-power broadcasting (FM/TV) antennas. Installing antennas in one site increases safety risks.
Take special preventive measures at antenna sites next to hospitals or schools.

Usage of Other Wireless Equipment

Apply the safe distance from electromagnetic field exposure specified by any related equipment manual.
Such distance is not specified for equipment with low RF transmit power that meets electromagnetic field exposure requirements.
Such distance is not specified for specially-designed equipment that meets electromagnetic field exposure requirements for working in close proximity.

Usage of High-voltage Equipment or Facilities

Since only high voltages (such as over 100 kV) generate harmful electromagnetic fields, the usage of such equipment or facilities must be evaluated according to requirements.