UV Output on T8 Lamps

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stevethecanadian

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We are designing an Archives project and the owner/government has requested that the lamps not exceed "75UV per lumne".

I'm assuming the spec above is worded incorrect or meaningless. But my thoughts are to send the owner the lamp data and have them comment on it, but the manufacturer's are dodging the question.

Does anyone know what the UV output of a standard F32T8 lamp puts out or where that info can be found?
 
Re: UV Output on T8 Lamps

I found a web site that addresses the specifications your after. It's probably mostly by accident that anybody who isn't already in on the secret industry jargon mumbo jumbo can find out anything.

You're right, UV is probably not what is meant. In museums and archives though it seems there is a specification for 75 IlW/lumen or less. (I think it's big I and little L but the L could be the number 1 too) I guess W means UV radiation.

I have absolutely no idea what any of this means but it sure sounds impressive. There are also W filters that will further reduce the W.

Anyway here's a link that doesn't seem to be coming out as a link so you may have to punch it in the old fashioned way.

:cool: UV Shades

Selecting Fluorescent Lamps for W Output

palimpsest.stanford.edu/byorg/abbey/an/an16/an16-4/an16-406.html

[ October 08, 2004, 04:58 AM: Message edited by: physis ]
 
Re: UV Output on T8 Lamps

You might try PHILIPS.LIGHTING.COM and request a technical guide on fluorescent lighting.
Philips' tech manuals were circa 1989 when I did research on UV exposure fade rate effects on artwork. There is a complexity of determining UV level outputs from fluorescent lamps because each color phosphor coated tube has different characteristics that mask the radiated UV wavelength intensity factors.
I do not recall a "UV per Lumne" terminology but I've not kept up to date with those advances. My question would be...Is it a maximum figure for blocking or increasing UV?
(I.e. Needing a controlled UVA/UVB radiation level would apply to a tanning facility.)
At the time when I did a comparison of the UV level/radiated watts of each standard Phosphor fluorescent light I also interpolated the reflected change effects to fabric colors and their fade rate comparisons. That info came from the American Textile Association. Another source is ELECTRICAL ENGINEERING REFERENCE MANUAL by Raymond B. Yarbrough (Professional Publications, Belmont, CA.)There is an in-depth analysis on lighting systems design Ch.13 'Illumination and the NEC.'
 
Re: UV Output on T8 Lamps

That list is a great starter. I will be pounding the manufacturer today to get the testing results of wuv/lumne for the lamp we are using.

Yes the intent is to limit the uv in the storage area.

It sounds like we will be ok using a standard lamp.

I was scared because we desiged to 30fc and if we had to change lamps we could have been in trouble.
 
Re: UV Output on T8 Lamps

The unit of measure that the specification is using is ?Microwatts per Lumen.? This is also the unit of measure displayed by a ?UV Meter.? It tells you the percentage of ultraviolet in the light that the meter is measuring.

The confusion over the symbol of the unit of measure is that the symbol for ?micro? is the lower case Greek letter ?mu.? What the document would have shown is ?mu W / lumen,? with the W meaning ?Watts.?
 
Re: UV Output on T8 Lamps

Charlie, I was initially thinking the UV may be microvolts. What I found was that the variables being used at the site I referenced are entirely unrecognizable to me. W is some kind of industry term or something for radiation, not watts. Everything I'm talking about comes from this one site, take a look at it. I may have just bitten into a bad apple. :(

I was expecting the nomenclature to be more like what you're talking about.
 
Re: UV Output on T8 Lamps

IES handbook 9th edition, figure 14-3 for museum applications lists incandescent at 75 UV (microW/lm) and lists fluorescent as lowest of 80 and high of 280. There's a lot of information concerning this in this book.
 
Re: UV Output on T8 Lamps

Originally posted by nvcape:. . . figure 14-3 . . . lists incandescent at 75 UV (microW/lm) . . . .
Click to expand...
Just so we remain clear on the units of measure, the column you cite from Figure 14-3 gives the UV content in units of (micro W / lm). In other words, ?UV? is not a part of the name of the unit of measure.

So rather than it saying incandescent is ?75 UV (micro W / lm),? what it is saying is that the UV of incandescent, in units of (micro W / lm), is 75.
 
Re: UV Output on T8 Lamps

physis, It's really not that easy. What you saw on the Stanford.ed website was misleading for sure. The formula reference 75 IIW/lumen refers to the initial illumination level (II) in Watts from the coefficient of utilization for calculation of maintained illumination. Without getting into explaining lumen depreciation levels,as
 
Re: UV Output on T8 Lamps

Gndrod, I haven't looked at light frequencies in some years but your mentioning the range of fluorescent makes me curious about what color 380 nm is. If I remember right green's in the mid 400's and blue's in the mid or late 500's. Would I be correct if I put 380 nm at yellow a little towards orange?

[ October 11, 2004, 01:16 PM: Message edited by: physis ]
 
Re: UV Output on T8 Lamps

physis, yes and no depending on the spectral reflectance of light. The 380nm wavelength is borderline violet in visual perception as in a blacklamp or the UV invisible band. The UV color that I was refering to was the altered 380nm fluorescent output that is altered by the rare earth phosphors masked coating in the tube. This is not the same color vibrations (waves) our eyes see from white light energy. (i.e. yellow wavelength is 570 to 590.) When we see a yellow object we are seeing the product of what was reflected from the yellow object less all the other wavelengths that were absorbed into that object and not reflected. The chart I made only shows the radiated power that gets through the mask on the tube. So back to looking at the list of phosphors for UV fading rates is catorgorized in the D, CW, CWX etc. intensity base. Now for these fluorescent color effects, this is where the Color Rating Index defines the optimum ability of these masks to show fluorescent reflected colors accurately. The Deluxe Cool White in the chart was the closest (87 CRI)to reflect a true hue as a dull white (best choice) without the mask altering a white fabric. In a Warm White tube the same 380nm will be masked to change the reflectance of the white fabric to a yellow white. In sunlight the fabric is reflected white as it is the combination of all the light energy colors. So there is a compromise as to UV fading and choice of good color reflected effects that the Deluxe Cool White has over other masks. Therefore fluorescents can be made from 2000 to 6500 kelvin color effects CT range(Color Temperature color of light.) Incandescents have limited visible light color by the various filament/gas properties for effects on reflected surfaces but have a better CRI reflective value at their operating color range. Tungsten is warm red-orange where a halide is blue on the
 
Re: UV Output on T8 Lamps

dang..I keep hitting a mystery button. Anyway, Art galleries use incandescents because of their better color reflective properties. I believe there is a Natural fluorescent that is the next step up from the Deluxe Cool White. The output will still be emitting at a UV wavelength close to 380 nanometers.
 
Re: UV Output on T8 Lamps

Physis, I didn't have time to finish last night on UV. There are filters that reduce the damage from the 220 to 380 UV range but also reduce the phosphor excitation light output. The Stanford.ed Abbey Newsletter article started with explanation of the illumination phenomena of selecting the high and low W outputs but didn't get into the physics of spectral emission properties of phosphors. I don't know of any explanation of how this happens other than differences in rare earth formulas can vary the 400 - 700nm visible range tints from the phosphor resonance lines. Maybe someone out there reading this has the expertise and can jump in and help out in this area.
The Table 1 chart gives a good example of how much efficacy difference exists to accomplish visible white light in comparable ranges between manufacturers.(I.e. CWX) The chart end columns equate percent visible MicroW UV per lumen in the graduated order of the UV level of radiation. I would definitely avoid using a Philips WWX for archival lighting at 5.82% as compared to GE's WWX at 2.00% visible UV. Unfortunately the chart doesn't include VariluX and the UV Gold Blocker filters.

rbj
 
Re: UV Output on T8 Lamps

Yeah, I'm getting colors and frequencies backwards. Can you just gimme the typical color range for fluorescent, or typical fluorescent?

I think your "mystery button" might be TAB. I'm not gonna test it but I think I've had that problem with it.
 
Re: UV Output on T8 Lamps

The most common fluorescent used are cool whites followed by warm whites depending on the mood intended. At one time I worked for an energy management firm where an F40 change to F32T12 with ballast switch out was done on commercial high rise. All tubes were CW. In residential, Warm whites seemed to be a favored choice. I've been installing T8 Electronic Ballasts with CW's for a high lumen low W consumption. The EB's are about 20% more efficient compared to the Magnetic type.

rbj, Seattle
 
Re: UV Output on T8 Lamps

Physis, What I think you are asking is a big order. I devised a chart from data given in the American Textiles Manufacturer's Association book I researched over 18 years ago. The Textile Finishing & Color Processes article listed 22 different colors along with eight different lamps popular in the late 1960's when the lighting change effects analysis was made.
That's 176 color exposure combination comparison's in a graph that is too lengthy to chart here. I have not figured out how to link the scanned page 70 MGI software of my wiring book for this post.
I can give you an idea for the fluorescent yellow-white range on a few of fabric colors such as orange, yellow and blue colors. The reflections are ranked in four trueness categories...Enhanced, Good, Fair, and Dull.
WW...orange=fair, Yellow= Good, Blue= Dull
D...orange= Dull, Yellow= Dull, Blue= Enhanced
SW...orange= fair, Yellow= Good, Blue= Dull
CWX..orange= fair, Yellow= fair, Blue= fair
Of course this chart won't demonstrate the differences that a light box does at your local light jobber. The good fixture (luminaire) rep will have a comparison incandescent and fluorescent light box that will reflect the fabric sample color difference you can expect from the lamps available now.
 
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