Optimal and most suitable lighting “color” for education of facilities 3000K-5000K?

[Fred B]

I bet that there will be no conclusive information that 3.5K or 4K or 5K is better, but if you can arrange some way to allow the individual teachers to change the color temperature and brightness in their rooms then they will be happier.

An art classroom might want closer to 5K whereas a standard classroom wouldn't be bothered by 3.5K vs 4K. It's the lumens, or intensity, that really matter, the K value really only effect color perception.
Think about incandescent lights and the old yellow vs the daylight or bright blue ones both could be 65watt and essentially provide the same intensity but what things look like due to color saturation would look different.

 

[NEC Inspector]

A small private school I was involved with changed all of the lights to 5k because they thought that would help students with vision problems. They found out that the 5k bulbs gave one of the teachers migraines. So back to 4k we went.

 

[James L]

However, there is one Board member wanting to change the specs back to 3500K as a personal preference. We need convincing proof that level of light is not adequate for the students and the learning environment.

Somebody needs to come at him like Moe, and treat him like Larry or Curly with a good smack on the back of the neck

I'm wondering, in what kind of backwards setting does a whole fleet of seasoned professionals have to invest an untold number of hours, in an effort to overcome the whims of a bureaucrat's personal preference?

 

[James L]

An art classroom might want closer to 5K whereas a standard classroom wouldn't be bothered by 3.5K vs 4K. It's the lumens, or intensity, that really matter, the K value really only effect color perception.

At my son's school, their art room I had fluorescent 735s

3500k with a 70 CRI
My goodness, the green hue was astounding.

I put in LED flat panels with somewhere around an 85 CRI and selected 4000k and it was a dramatic improvement

It was really the CRI that made the difference

 

[Abi F.]

Every classroom we retrofit with 4K at 80 CRI minimum, the teachers and students are very thankful, and the change is very much appreciated!!

Hopefully an educated resolution is made based on facts and not personal preference for the benefit of the students and teachers.

 

[Fred B]

Wish I could find a legitimate accurate method to have a comparative transition calculation to go from Florescent to LED. Had an auditorium that everyone was happy with color and brightness of the Florescent, but when getting identical numbers for the LED color and wattage, the LED was way brighter, even when I went from 4000K Florescent to 2800K LED, the LED were still brighter, both were 35Watt equivalent.
Another interesting effect was the LED would cause a flicker roll on the camera view but the florescent never did. Not sure why.

 

[Knightryder12]

Our school district is or was looking at tuneable light. They were looking at controlling the color temp throughout the school day to mimic the sun. Starting off with a really warm light in the morning and going up to 5K throughout the day and than tuning it down towards the end of the school day. Never heard if that has become the standard or not.

 

[winnie]

Our school district is or was looking at tuneable light. They were looking at controlling the color temp throughout the school day to mimic the sun. Starting off with a really warm light in the morning and going up to 5K throughout the day and than tuning it down towards the end of the school day. Never heard if that has become the standard or not.

That sounds like a great idea for a research project to try out and see if it offers any real benefits, and horribly unsupported as to actual known benefits.

I'd totally go for it as an architectural concept and reject it as science.

-Jonathan

 

[Flicker Index]

There's no one answer.
I was once at a retail parking lot tent sale with LED type lights. They did a good job lighting up the ground, but provided very very little vertical FC, so products were not lit well at all.

You talked about CCT but ignored the hardness of light. See

if you need explanation (sorry if you get stuck with some lame ads)

"hard" light is almost always undesirable, because they cause shadows and multi-faceted shadows are especially bad.

 

[Fred B]

Our school district is or was looking at tuneable light. They were looking at controlling the color temp throughout the school day to mimic the sun. Starting off with a really warm light in the morning and going up to 5K throughout the day and than tuning it down towards the end of the school day. Never heard if that has become the standard or not.

This is becoming a normal for some health care facilities long term care.