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Radiation in the Workplace

In this section:

• Aircrew exposure
• Laser pointers
• Office equipment
• WiFi networks

Aircrew exposure

Information on exposure of passengers and aircrew to cosmic radiation during air travel can be found in: Cosmic radiation and air travel (PDF - 123 kB).

Particular information on aircrew exposure is contained in IS 19  The exposure of New Zealand aircrew to cosmic radiation.

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Laser pointers 

Used as presentation aids by speakers and teachers, laser pointers have become increasingly common over the last decade.  Their increased availability and use as a cheap novelty item raises the possibility of accidental or deliberate misuse, making them a hazard.

Laser pointers currently available emit a very narrow beam of red light, which diverges only slightly with distance.  It can be concentrated into a tiny spot and can cause permanent damage if the laser is shone straight into the eye.

Although the risk of permanent damage from a laser pointer is small, temporary effects are more common.  Momentary viewing of the beam from a laser pointer may cause distraction and temporary loss of vision.  NRL recommends that only Class 1 or Class 2 laser pointers be used, and that laser pointers should not be given to children as toys.

Further information can be found in NRL Information sheets. IS 24  Safe use of laser pointers and IS 20  Laser safety, which gives more detailed information on the laser classification scheme.

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Office equipment

If there is a lot of office equipment (computers, fax machines, laser printers etc) together in a small area, do they produce dangerous levels of radiation?
No. Like any other electrical appliance, the voltages and currents in modern office equipment produce electric and magnetic fields, which are not a form of radiation. Measurements have shown that the strengths of the fields to which office staff are exposed are generally unaffected by the number of pieces of equipment in an office, and that they are well below health-based exposure limits recommended in New Zealand and overseas.

For more information go to:
IS 17  Emissions from visual display units (VDUs) 
IS 23  Computer display (VDU) interference from power cable magnetic fields.
www.who.int/inf-fs/en/fact201.html Fact sheet 201 of the World Health Organization.  This information sheet provides information on emissions from VDUs and human health implications.

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Exposures to radiofrequency fields from WiFi networks

WiFi (wireless fidelity) networks provide data connections between computers, either direct computer-computer links or to connect a computer to a network.  They may be used to replace cable connections in the home, school or office, or to provide mobile internet access through so-called “wireless hot spots” in cities, at airports and in other locations.

WiFi uses a radio signal to transfer data over the link.  Because the system is only intended to work over short distances (a few tens of metres) the transmitters at the wireless access point and in the computer need only operate at low power.  Typically, the transmitter power is less than 100 milliwatts – similar to that used by a cordless or mobile phone.

Exposures to the radiofrequency fields generated by WiFi equipment are very low, for three main reasons:

• The low power of the transmitter
• The rapid decrease in signal strength with increasing distance from the transmitter
• The fact that the transmitters are turned off when no data is being transmitted.

Measurements in New Zealand and overseas show that exposures are typically around one hundred thousand times lower than the exposure limit recommended for the public in the New Zealand radiofrequency field exposure Standard[1].  This Standard is based on guidelines published by a scientific body recognised by the World Health Organisation for its expertise in this area, and includes a safety factor of fifty in the public limit.

For comparison, the exposures are similar to ambient levels measured in central city areas from commercial TV and radio broadcasting transmitters.

In its fact sheet Base stations and wireless technologies, the WHO states:

“From all evidence accumulated so far, no adverse short- or long-term health effects have been shown to occur from the RF signals produced by base stations. Since wireless networks produce generally lower RF signals than base stations, no adverse health effects are expected from exposure to them.”

The UK Health Protection Agency states:

“There is no evidence to date that exposure to the RF signals from WiFi and WLANs adversely affect the health of the general population.”

The National Radiation Laboratory considers that the health research carried out to date shows that working and studying in areas with WiFi equipment poses no health and safety risks to adults or children.  Although no special precautions are needed, if individuals are concerned and wish to reduce their exposures, they can take simple steps to do so:

• Place the wireless access point up on a high shelf or away from where people might sit and work.
• When working with a WiFi-enabled laptop, place it on a table rather than directly on the lap.

The National Radiation Laboratory is carrying out further measurements on WiFi systems and more data will be made available when this work is completed.

[1] New Zealand Standard 2772.1:1999 Radiofrequency Fields Part 1:  - Maximum exposure levels 3 kHz - 300 GHz

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