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CRI STANDARD FOR SITE LIGHTING?

CRI STANDARD FOR SITE LIGHTING?

CRI STANDARD FOR SITE LIGHTING?

(OP)
I would like to know what is  the commonly used CRI by any standards? Is CRI> 85 fir site lighting is too much to ask.

Can some one refer me as to where I can look  this up?

RE: CRI STANDARD FOR SITE LIGHTING?

I'm not aware of any standards that would prevent you from putting in nothing but orange sodium lighting or red neon lighting if that's what you wanted to do.

Put in whatever CRI source you like.

RE: CRI STANDARD FOR SITE LIGHTING?

PS -- Energy codes might prohibit incandescent lighting (which is the only 100 CRI source I'm aware of, but other sources are getting better all the time).  Verify against the applicable ASHRAE 90.1 or IEC energy codes if in effect in the jurisdiction in question.

RE: CRI STANDARD FOR SITE LIGHTING?

(OP)
When the CRI exceeds 80, the light gets much warmer. 80 is some thing good for interior lighting, usually achieved by fluorescents lamps.

When CRI [Color Rendering Index] exceeds 80, it is  usually used for bringing up the colors like in a  meat department in a grocery store or clothing store etc.

The higher the CRI, it gets much costlier and normally these warmer lamps are used for interior applications only.

The original question was whether it is worth going for a  high CRI for something like a parking lot  etc.. and pay a much higher price?

I have no access to ASHRAE-90.1 to find out what it recommends for site lighting>




 

RE: CRI STANDARD FOR SITE LIGHTING?

There is no standard for exterior lighting wether it be parking lot lighting, landscape lighting or building facade lighting.  There is however some types of lighting that is either specifically not wanted in certain areas but highly recommended in others.  The CRI of metallic halide sources can be closely controlled by using coated lamps and even ceramic lamps, but it really is not that critical.  Where color rendition is of a critical nature is in security applications.  Many police organizations do not allow use of low pressure sodium lamps because it is impossible to note the color of vehicles, clothing etc..., under this source.  In fact even HPS is not recommended for areas under CCTV supervision due to poor contrast and color rendition.  On the opposite side of the spectrum here in Southern California for example, we have what is known as the Mount Palomar dark sky zone which is a fifty mile radius around the Mount Palomar observatory wherein all exterior lighting which is to be on after a certain hour must be LPS.

What you should decide is how important it is for you to be able to tell the color of whatever it is you are lighting and how much light you will need.  If for example you are lighting a building facade with advertising or corporate logos, then you should use an MH fixture with a CRI of 85 or so.  If the colors are mostly greens and blues, then a lower CRI will suffice.  It really does bring the "Design" part of lighting design to the fore.

Good luck with your search.

RE: CRI STANDARD FOR SITE LIGHTING?

Sometimes, lamp color rendition for exterior lighting like site, parking, and building illumination are governed by zoning codes.  This is typically the upscale neighborhoods with some sort of review board for projects or buildings.

Don Phillips
http://worthingtonengineering.com

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