Why is light important?
Light has a direct effect on your eyes and an indirect effect on your concentration. Too weak light stresses the eye muscles (constant re-focusing), resulting in rapid fatigue. You may know this effect from reading a book with dim lights.
The same effect happens when high precision tasks like pipetting are to be done – resulting in a higher risk for errors like swapped samples or wrong volume settings. Too bright light has similar effects.
The illuminance of light can be measured. This light power is the summed-up luminous flux incident on a surface. The luminous flux is measured per base area.
The illuminance is measured in lux [lx]. An alternative unit is "lumens per square metre" [lum].
In some countries, a non-metric unit of illuminance is used, the foot-candle [fc].
Color of light
The color of light is measured in Kelvin. Based on EN 12464-1, three areas can be differentiate
- warm-white light:below 3,300
- neutral white light: 3,300 to 5,300
- Day light white light: above 5,300 K
Type of light sources
Standard bulb versus neon lamp versus LED
Light power at working area
The EN 12464-1 provides some information about minimum light power at standard working spaces.
Office desks should have in general at least 500-1,000 Lux.
Technical drawings shuld be done with at least 750 lux.
For laboratory work there are currently no official recommendations, but the 750 lux should be a good starting point.
Keep in mind to have more light for high precision tasks (compare to doctors at surgeries!)
If working with electronic instruments like centrifuges or pipettes adjust the brightness of the display. Too bright displays in a dimmed room may disturb the eyes.
Natural day light
Never forget: The best light comes from outside!
Daylight with it`s unique spectrum regulates physiological processes as well as the circadian rhythm of humans.
Thus a good laboratory has big windows with blinds against direct sunlight.