LED "Daylight" bulbs

"Daylight" tends to mean high colour temperature (5500 - 6500K).

There are often two problems with this when used for artificial lighting:

The intensity is nowhere near what your brain expects for this colour temperature, so it looks wrong and makes colour perception (particularly in the reds) more difficult. Raw meat preparation is the classicly bad match for such a situation.

Some of these high colour temperature LEDs have poor colour rendering properties. Again, if discrimination by colour (not racial discrimination;-) is part of the job, it could be that this is now much harder to do.

What is her job?

Another potential issue - if the lamps are dimable on regular dimmers (even if not used in this case), many such LED lamps flicker at 100Hz. That's not a problem normally, but if you are looking at things which move under 100Hz strobe, it might be.

Flicker or perhaps a spectrum problem. Its surprisingly easy to fool the eye that light is white when it is actually not.

Brian

In article , EricP writes

She'll need to wear sunglasses until the management realise their mistake. Seriously, they'll get the message eventually and the sunnies will help reduce the effects in the mean time. Don't vocalise too loudly about the problem but if asked, do mention that the glasses are needed to stave off blinding headaches that started when the new lamps were installed.

You can get sheets of daylight>warm white converting filters quite cheaply. Might be worth a try, if only as an experiment

Probably flicker - too fast to be noticeable. Although I'm surprised it's effected everyone.

It's a social club. Just the usual large room with dormer type windows and a bar at one end. It has always has quite nice low level lighting brightening at the bar

What you have said has exactly confirmed the ideas of a sparks that is a regular and a few others.

Many thanks for your good input. :)

Good idea about that. Hopefully they can get it looked at soon. :)

Its a yellow filter , it`ll just lower output by quite a lot.

Warm white LEDs use a differnt phosphor mix to cool white.

Sounds like crap, I do not believe it,they need psych evaluation good fodder for some cult.

Any nasty vapours being given off by the lights or the power supplies? Varnish on circuit boards overheating?

Anything in the building been disturbed? EG Could there be a leaky boiler flue above a ceiling, which has been disturbed to install the lights, and CO is now getting into the workplace?

Owain

I changed ALL of our lights to daylight ones and it's one of the best things I've ever done. The light is far more pleasant and superior. We haven't had a headache since the change.

Just found this:

The Workplace (Health, Safety and Welfare) Regulations 1992: Regulation 8 requires every workplace to have suitable and sufficient lighting. The lighting in the workplace, should as far as is possible, be natural.

and this:

The Management of Health and Safety at Work Regulations 1999 place a duty on employers and self-employed people to assess risks to health and safety from their undertaking. This will include risks from lighting.

- Mike

Also found this:

- Mike

For 'daylight' I prefer 4000K - 4500K (nominally moonlight in thickypedia). It is bright and clear without any trace of blueness. So far I've found only

I see.

Are you sure that its the lights and not a duff batch of beer?

All my main lights are now daylight LED and I too prefer them. However, my preference could be age related - as I get older my eyesight is not as good as it once was and I find that daylight type LEDs give better perceived contrast and make reading etc. easier.

Yes it does seem strange to get headaches from daylight bulbs. They have a much better spectrum for the eyes. It's certainly the first I've ever heard of getting headaches from them.