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Computer/VDT Screens Q
Do computer screens emit radiation that is harmful to the eyes?
A
According to the American Academy of Ophthalmology (AAO), "there is no
convincing scientific evidence that computer video display terminals (VDTs)
are harmful to the eyes." The common complaints of eye discomfort and
fatigue are associated with ergonomic factors such as distance from the
person to the monitor, monitor height and brightness, etc.
Q
I have a colleague who is pregnant and who types at a computer. How much
radiation does her baby receive at a typical computer? Is there a lead
shield that she could wear? Like an apron?
A
Regulations of the US Department of Health and Human Services require
manufacturers to test computer monitor emissions for radiation and to label
them attesting to the fact that they have been found to meet the standards
of Title 21 of the Code of Federal Regulations. You should be able to find
this label on the rear of the computer monitor or the computer processor.
Health studies of pregnant women who work with VDTs have not found harmful
effects on the women or on their children. Heavy lead aprons or other
shields are not considered necessary for units that meet the x-ray emission
standards of 21 CFR. Such shields may actually be counterproductive from an
ergonomic point of view.
Q
What amount of exposure is received from the average computer monitor?
A
Radiation emissions from VDTs (for example, television sets and computer
monitors) are regulated by the US Food and Drug
Administration<http://www.fda.gov/cdrh/devadvice/311.html>(FDA) and
manufacturers are required to test and label these products.
Regulations limit radiation emissions from electronic products to levels
considered safe.
Q
I have heard a lot of answers about the ill effects of computer radiation
but almost all that I have read claim no certainty in their answers. Has
there been any valid and indisputable answer to this?
A
The consensus of the authoritative reports I have seen is that scientific
studies have been unable to verify and reproduce any of the reported health
effects of ambient levels of electromagnetic fields from powerlines or
electric appliances. The inability of more recent studies to reproduce the
originally reported effects of electromagnetic fields indicates that those
early findings may have been unique in some way, possibly due to statistical
clustering, and are not generally applicable to other places and times.
This means that if there are health risks they are too small or of a kind
that have not been detected by current methods. Scientists often say that
they "cannot disprove a negative," meaning that it is not logically possible
to prove that something does not exist. This is because the list of things
to be disproved can be endless, and the type and level of sensitivity of the
tests that are used can always be improved upon.
Q
I'm getting a computer for my child and would like to know which type of
monitor/computer is safest in terms of the different types of radiation that
exist. I was told years ago that the flat screens had a different, yet
worse, type of radiation. Are there two types of radiation, and is this type
worse?
A
All television receivers (including computer monitors), regardless of type,
must meet a mandatory federal performance standard so any x-ray emissions,
if they exist at all, must be at very low levels. I am unaware of two types
of radiation, unless you categorize the visible light which you see on the
television screen as one type, which is, in fact an electromagnetic
radiation; You can also consider radiowaves, which are also electromagnetic
radiation. Both of these types of radiation are nonionizing and generally
considered safe unless one is exposed to very intense levels.
Q
How safe is it to work sitting right at the back of the monitor of a
computer workstation?
A
All television receivers (including computer monitors), regardless of type,
must meet a mandatory federal performance standard so any x-ray emissions,
if they exist at all, must be at very low levels. The key point is that the
emission standard is for "any point on the external surface" which means
whether someone is in front of, to the side of, or behind the display or
receiver, he/she is protected against any potential emissions of the display
to the same degree.
Q
My mom worries about the effects of computer radiation. She says that I am
putting my health at risk by being on my PC more than four hours a day. Is
this true?
A
The radiation emission from any computer is RF (radiofrequency) waves. There
is no proof that these are harmful unless the intensity is high enough to
warm tissue (like a microwave oven). You are not putting yourself at risk
(from radiation) by being on your computer more than four hours a day.
Q
My grandchildren often sit with their laptop computers in their laps. Is
there any danger to their health and reproductive organs from low-level
radiation that may be reaching them?
A
The only measurable radiation emission from a laptop computer is radio
waves. We are constantly exposed to such radiation from all directions and
multiple sources, including radio and TV signals, electronic appliances,
etc. Current data indicate that these are not harmful to our health. There
is, however, quite a bit of heat generated within the laptop while it is on.
It is for this reason manufacturers recommend against extended periods of
use with the computer on your lap.
The information and material posted on this Web site is intended as general
reference information only. Specific facts and circumstances may alter the
concepts and applications of materials and information described herein. The
information provided is not a substitute for professional advice and should
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whatever facts and circumstances are presented in any given situation.
Answers are correct at the time they are posted on the Web site. Be advised
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