Questions and Answers

Questions and Answers on Light Pollution

We can measure horizontal and vertical lighting through some software programmes....how do we measure the upward lighting...

From LCS, UL can be known

Any comments on properly measuring lighting with tools and in the case of spectroradiometers that a proper light curve is used, so that the blue spectra of the light is measured properly. Comments?

Handheld spectrometer can give blue light spectrum on computer screen

Great insight Sir. Any regulatory body in place for Light pollution in India as i understood that there is no IS standard in place as of now?

In NBC Light pollution is addressed but no regulatory body appointed.

Since lightining pollution cannot be avoided and can be reduced only, is there a standard which clearly specifies the limit of tresspassing light into nearby objects or building?

Yes -MLO and IESNA

Which is the best suitable colour for indoor working in assembly shop?

4500K should be better option. But 4500K to 6000K can be selected as per application

Does the light pollution depend on CRI of light fixture? How to select a good quality LED source.

Role of CRI depends upon application but fixture where in it is used plays role in pollution.  From pollution prospective less or no blue light emission by LED is better option. Good quality of LED can be on basis of lumens per watt, CRI, life, test reports, reputed brand etc.  

Crescent moon sightings form an important occurrence for marking of a new lunar month.

Yes

is the best suitable color for indoor working like assembly, workshop etc

4500K should be better option. But 4500K to 6000K can be selected as per application

How efficiently can this be done within the horizon levels and a city lit skyscape?

Highly efficiently it can be done provided stringent rules are made and entire city or province participate in program.

Are 6000 K lights more polluting?

Generally more than 6000K+ emits more blue light hence more pollution.

Turning off the lights is a challenge in the current scenario due to safety, increasing crime rate.Like you mentioned dimming, Dont you think providing lighting controls in all streetlighting solutions, should be a mandatory requirement for any projects?

Yes

Which type of Highbay light shape is ok?

Round in factories, open type of warehouses, highways and linear in ware houses having aisle, stores and square for flood lighting

Rectangular light fixture or round light fixture..which one is best for equal lux level distribution on floor to enhanse more lights without glare or light pollution?

This depends upon mounting height but round can be better depends upon design and calculation.

Is CRI index affect light pollution and is 6000k lights more polluting

Yes, as long as you realize the required 1000 lux at the eye of persons that in the environment

Upwards reflection of light as a cause of light pollution and light trespass is not considered in the BUG specifications. Where is that problem considered?

Back-Forward light High and very high of each contributes Tress pass