Recommended illuminance Levels for Various Tasks/Activities / Locations

Recommended Illuminance Levels for Various Tasks/Activities/ Locations

(A) Recommendations on Illuminance :

Scales of illuminance :

The minimum illuminance for all non-working interiors, has been mentioned as 20 Lux (as per IS 3646)
A factor of approximately 15 represents the smallest significant difference in subjective effect of illuminances.
Therefore , the following scale of illuminances is recommended. 20-30-50-75-100-150-200-300-500-750-1000-1500-2000…. Lux.

Illuminance ranges :

Because circumstances may be significantly different for different interiors used for the same application or for different conditions for the same kind of activity, a range of illuminances is recommended for each type of interior or activity intended of a single value of illuminance.
Each range consists of three successive steps of the recommended scale of illuminances. For working interiors, the middle value (R) of each range represents the recommended service illuminance that would be used unless one or more of the factors , mentioned below apply
The higher value (H) of the range should be used at exceptional cases where low reflectances or contrasts are present in the task , errors are costly to rectify, visual work is critical, accuracy or higher productivity is of great importance and the visual capacity of the worker makes it necessary.
Similarly, lower value (L) of the range may be used when reflectances or contrasts are unusually high speed and accuracy is not important and the task is executed only occasionally.

(B) Recommended Illumination :

The following Table A gives the recommended illuminance range for different tasks and activities for chemical sector.
The values are related to the visual requirements of the task to user’s satisfaction to practical experience and to the need for cost effective use of energy.
For recommended illumination in other sectors, reader may refer lluminating Engineer Society Recommendations Handbook . confirms

Chemicals :

Petroleum, Chemical and Petrochemical works

Exterior walkways, platforms, stairs and ladders 30-50-100

Exterior pump and valve areas 50-100-150

Pump and compressor houses 100-150-200

Process plant with remote control 30-50-100

Process plant requiring occasional manual intervention 50-100-150

Permanently occupied work stations in process plant 150-200-300 200-300-500

Control rooms for process plant 200-300-500

Pharmaceuticals Manufacturer and Fine chemicals manufacturer

Pharmaceutical manufacturer Grinding, granulating, mixing, drying, tableting, sterilising, washing,

preparation of solution, filling, capping, wrapping, hardening 300-500-750

Fine chemical manufacturers

Exterior walkways, platforms, stairs and ladders 50-100-150

Process plant 300-500-750

Fine chemical finishing 300-500-750

Inspection 300-500-750

Soap manufacturer 200-300-500

General area 100-200-300

Automatic processes 200-300-500

Control panels 200-300-500

Machines 200-300-500

Paint works

General 200-300-500

Automatic processes 150-200-300

Control panels 200-300-500

Special batch mixing 500-750-1000

Colour matching 750-100-1500

Case Examples :

Energy Efficient Replacement Options :

The lamp efficacy is the ratio of light output in lumens to power input to lamps in watts. Over the years development in lamp technology has led to improvements in efficiency of lamps.
However, the low efficacy lamps, such as incandescent bulbs, still constitute a major share of the lighting load. High efficacy gas discharge lamps suitable for different types of applications offer appreciable scope for energy conservation.
Typical energy efficient replacement options, along with the per cent energy saving, are given in Table A

Table A : Savings by use of high efficacy lamps

Wattage of CFL includes energy consumption in ballasts.

Energy Saving Potential in Street Lighting :

The energy saving potential, in typical case of replacement of inefficient lamps with efficient lamps in street lighting is given in the Table B.

Table B : Saving potential by use of high efficiency lamps for street lighting