Light ergonomics
Encyclopedia
Light ergonomics is the relationship between the light source and the individual. Poor light can be divided into the following:
- Individual or socio-cultural expectations
- Insufficient light
- Poor distribution of light
- Improper contrast
- GlareGlare (vision)Glare is difficulty seeing in the presence of bright light such as direct or reflected sunlight or artificial light such as car headlamps at night. Because of this, some cars include mirrors with automatic anti-glare functions....
- Flicker
- Thermal heating (over or under)
- Acoustic noise (especially fluorescents)
- Color spectrum (amber street lighting)
Effects of poor light
The effects of poor light can include the following:- low productivity
- high human error rates
- inability to match or select correct colors
- eyestrain
- headacheHeadacheA headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
- a reduction in mental alertnessAlertnessAlertness is the state of paying close and continuous attention, being watchful and prompt to meet danger or emergency, or being quick to perceive and act. It is related to psychology as well as to physiology...
- general malaiseMalaiseMalaise is a feeling of general discomfort or uneasiness, of being "out of sorts", often the first indication of an infection or other disease. Malaise is often defined in medicinal research as a "general feeling of being unwell"...
- low employee moraleMoraleMorale, also known as esprit de corps when discussing the morale of a group, is an intangible term used to describe the capacity of people to maintain belief in an institution or a goal, or even in oneself and others...
| Recommended Illumination Levels | |
|---|---|
| Type of Activity | Ranges of Illuminations (Lux Lux The lux is the SI unit of illuminance and luminous emittance, measuring luminous flux per unit area. It is used in photometry as a measure of the intensity, as perceived by the human eye, of light that hits or passes through a surface... ) |
| Public spaces with dark surroundings | 30 |
| Simple orientation for short temporary visits | 50 |
| Working spaces where visual tasks are only occasionally performed | 100 |
| Performance of visual tasks of high contrast or large scale | 300 |
| Performance of visual tasks of medium contrast or small size | 500 |
| Performance of visual tasks of low contrast or very small size | 1000 |
| Performance of visual tasks near threshold of person's ability to recognize an image | 3000-10000 |
Types of light sources
| Light Bulbs | ||||
|---|---|---|---|---|
| Type | Common Application | Efficiency | Colour Rendering | Fog-Smog Penetration |
| Incandescent Incandescent light bulb The incandescent light bulb, incandescent lamp or incandescent light globe makes light by heating a metal filament wire to a high temperature until it glows. The hot filament is protected from air by a glass bulb that is filled with inert gas or evacuated. In a halogen lamp, a chemical process... |
Homes | Poor | Good | |
| Fluorescent Fluorescent lamp A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful... |
Home&Office | Good | Fair to good | |
| Mercury Mercury-vapor lamp A mercury-vapor lamp is a gas discharge lamp that uses an electric arc through vaporized mercury to produce light. The arc discharge is generally confined to a small fused quartz arc tube mounted within a larger borosilicate glass bulb... |
Factories, offices | Fair | Fair to moderate | |
| Low pressure sodium | Roadway | Good | Poor | Good |
| High pressure sodium | Factories, commercial | Good | Fair to good | Good |
| Metal Halide Metal halide lamp Metal-halide lamps, a member of the high-intensity discharge family of lamps, produce high light output for their size, making them a compact, powerful, and efficient light source. By adding rare earth metal salts to the mercury vapor lamp, improved luminous efficacy and light color is obtained... |
Factories, commercial | Good | Good | |
See also
- ErgonomicsErgonomicsErgonomics is the study of designing equipment and devices that fit the human body, its movements, and its cognitive abilities.The International Ergonomics Association defines ergonomics as follows:...
- Full-spectrum light
- Artificial sunlightArtificial sunlightArtificial sunlight is the use of a light source to simulate sunlight where the unique benefits of sunlight are needed, but where sufficient natural sunlight is not available or is not feasible...