Health and Safety Issues in Use of Digital Media

SFSU Conceptual Information Arts Program     prepared by Stephen Wilson
url: http://userwww.sfsu.edu/%7Einfoarts/technical/cia.sfsu.healthandsafety.html

Unlike other art forms, working with computers and electronic media poses little risk of poisonous vapors.  You are unlikely to cut off your finger.  Still there are risks and dangers that you need to be aware of.  Also you should know good practices which can minimize these risks. The risks fall in these categories:


Eyes and Vision

Dangers
Good Practices
- The eyes were not designed for concentrated unwavering focus at a fixed distance
- Eyes blink much less when staring at video or computer screens and thus become dry
- Illumination levels can strain and stess the eyes and reduce visual acuity
- Bad contrast in ambient illuination can cause glare on the screen and fatigue the eyes
- Take mini breaks to focus on objects at various distances in the room
- Do figure 8 exercise with head letting the eyes change focus as the head moves
- Palming excercise - hold palms over eyes
- Ergonomics - Set up workstation so screen is level with eyes or at most 10" down  (** see illustration below)
- Make sure sunlight or bright lights are not directly behind you so there is no glare.  Better to be at the side
- Make sure the screen is not the only illumination in the room - turn on other lights or arrange for natural light
- Use a no glare screen


Fingers, wrists, and arms - Repetitive Stress Injuries (RSI) - Carpal Tunnel Syndrome


Dangers
Good Practices
- The arms and hands were not designed for fixed postions for long times. 
- The high impact, restricted motions of keyboarding and mouse movement create great stress
- Hands, arms, wrists are subject to Repetitive Stress Injuries (RSI).  These injuries represent nerve damage. In the worst cases, one can lose function in the hands.
- Carpal Tunnel Syndrome injuries occur when the nerves and muscles that pass through the opening called the carpal tunnel which connects the arms and the hands are subjected to continual restricted motion.
-Ergonomics. Set up the workstation so the elbows are roughly at 90".  (** see illustration below)
-Also the hands and wrists should be level - not bent up or down.  The mouse should be located near the keyboard.
- Take regular mini breaks. (every 10 minutes)
- Do hand and wrist excercises  (see U Maryland guide)
- Consider using an ergonomic keyboard - for example split so the they match the natural angle of the hands.

If you use a portable computer as your major work station with long sessions, consider using an auxillary keyboard so the ergonomics can be better adjusted




good ergonomic setup
Image from Computer Assistance program - workstation setup guide


Backs, shoulders, necks

Dangers
Good Practices
- Body was not designed for long term fixed positions
- Bad sitting posture can cause strain in head, neck, back, and arms
- Bad sitting posture can cause strain in legs
- Bad sitting posture can cause fatigue
- Take mini breaks with exercises (for example stretches, jumping jacks)
- Ergonomic setup - back, legs and knees should be roughly at 90". Adjust chair level and or keyboard level (**see illustration above)
- Feet should be firmly on the ground not hanging
- If working in temporary space such as university computer lab, bring pillows, boxes to elevate keyboard if adjustable furniture is not available.

Electromagnetic Radiation


Dangers
Good Practices
There is great debate whether long term exposure to low frequency (60hz) or high frequency (CRT scanning) radiation is dangerous to health. Scientific studies by neutral parties do not return consistent results.  Still there are anecdotal reports of higher instances of cancer and birth anomalies.  Most agree the dangers if there are any focus on those who spend the entire workday at the workstation. 

wiki article on hazards
CRT use high voltage electron guns to illuminate the screen.  The screens are usually shielded.  The backs and sides are not as well shielded.  One should make sure not to position near the back or side.  And a respectable distance from the front should be maintained.  Radiation falls off at the inverse square of the distance.  f=1/d2    (for example, being twice as far away means the radiation will the 1/4 the intensity.)

Consider using a radiation screen over the CRT.  (Flat screens are making much of this moot)


Ergonomics Web Resources