[Murugan]

Poll: Color Choice for Street Lighting

1. Sodium vapor lamp
2. Mercury vapor lamp
3. Other - please specify

While most street lighting (atleast in Chennai) is by sodium vapor lamps one still finds streets lit by mercury vapor lamps. Which one is better in your opinion for visibility in the night?

There may be other reasons for using one over the other: initial cost, running cost (read power consumption), maintenance, longevity etc. Please do not consider these parameters for the purpose of this poll.

[clevermax]

Of course MV Lamps are better since they have near white luminance compared to the boring yellow tone of SV Lamps.

On an afterthought, authorities could also think of using some bright CFLs instead of MV Lamps, since the power consumption will be much lesser. recently I replaced an aging 7 year old MV Lamp which lights up our garden (100 Watts) with a 25W CFL. It gives the same lighting.

[snaronikar]

In my opinion, MV lamps lights are better and have more luminance. I would always prefer this to SV lamps. The roads always always look better in MV lamps. :-)

[iraghava]

Yellow lamps are preferable as they are of some assistance during foggy condiditons also, where white lamps will be completely useless.

This is what I was told by representative sof Havell's when we were buying some street lamps to install in our premises.

[clevermax]

Originally Posted by iraghava

Yellow lamps are preferable as they are of some assistance during foggy condiditons also, where white lamps will be completely useless.

This is what I was told by representative sof Havell's when we were buying some street lamps to install in our premises.

You can't really see any yellow street lighting in winter countries where they have lots of fog and smog which sometimes affects visibility very badly. They all use white lighting.

But the point is right. Yellow is better in foggy conditions.

[setuniket]

I remember last winters Noida Authority guys initiated a drive to change all the SV lamps to MV ones, since then the look and feel while driving/riding has completely changed in late nights. There was no change in overall visibility(Due to the fact that there was no/less fog/smog this time) but it looked absolutely beautiful...

IMO MV ones looks far better than SV ones...

[Murugan]

Originally Posted by iraghava

Yellow lamps are preferable as they are of some assistance during foggy condiditons also, where white lamps will be completely useless.

This is what I was told by representative sof Havell's when we were buying some street lamps to install in our premises.

I am not sure if yellow lights are better in fog conditions. Please see the discussion in the link below.

http://www.team-bhp.com/forum/indian...-banned-4.html

If yellow lights are not of much use as fog lamps in cars, would they be of much use in street lighting?

http://www.team-bhp.com/forum/742082-post1486.html

[SirAlec]

It doesn't matter what type they use. Only concern is that they do a regular maintainance of each and every light.

[alpha1]

Mercury Vapor lamps are definitly much better for illumination.

I dont know how many ppl here are aware, but in all refineries/chemical plants/industrial areas/workshops they use MV for illumination.

MV's give a white light, with slight purple/violet tinge. Which is anyway more indicative of true color. Whereas the Sodium vapor gives only that orange wavelength - which doesnt allow you to see true color.

The only reason why Na lamps are used is because of low running cost - they consume less electricity.

Actually the ones that we see eon raods are the low pressure sodium vapor lamps. The high pressure ones give a better color range - with pink tinge. But I dunno exactly why they aint used over here in India.

[Chevy_lover]

I like the white colour of Mercury vapour lamps. I don't like it when the roads look yellow!!

[DirtyDan]

Originally Posted by Chevy_lover

I like the white colour of Mercury vapour lamps. I don't like it when the roads look yellow!!

Yellow does not penetrate fog or moisture any better than white. This is an "urban legend". In India it is not good to see anyone under a yellow light. It has another ominous connotation.

[girishglg]

Not sure which one is what

Mercury vapour - Orange light
Sodium vapour - White light

Is this correct?

In any case I like the orange light ones since it is a typical color of a street light.

[mpksuhas]

Originally Posted by girishglg

Mercury vapour - Orange light
Sodium vapour - White light

Guess its other way around.

[sohail99]

I would recommend LED street lighting with proper heatsinking and waterproofing!

That would save a LOT of electricity and the deficit will be reduced quite a bit!

+ Different LEDs can be used for either warm white(4300k) or cool while(5-6000k)

In foggy conditions, they can alter the lights easily to produce warm white or even slightly amber light which can penetrate the fog easily!

[Koenigsegg220]

Originally Posted by girishglg

Not sure which one is what

Mercury vapour - Orange light
Sodium vapour - White light

Is this correct?

In any case I like the orange light ones since it is a typical color of a street light.

Its the other way round
MV : Whitish light
SV: Yellowish( Or is it Orange ? ) light