rworth at oda.state.or.us
Thu Jun 28 12:57:15 EDT 2001
Have there been tests done on the effectiveness of different tubes
when combined with different white sheet configuations? I'm thinking
primarily of the increased effectiveness of using a parabolic sheet
set-up as I saw discussed in the Masters thesis of Noel McFarland,
OSU, 1963. The idea, as I understand it, is to keep the moths
around for a longer period without the use of a trap.
>In a message dated Wed, 27 Jun 2001 10:28:46 PM Eastern Daylight
>Time, "JH" <jhimmel at CONNIX.COM> writes:
>Hi folks - A friend mentioned to me that he has been seeing very
>few moths at his lights in northern Pennsylvania. He read on the
>package of his UV bulb (one of those semi-circular tubes) that they
>loose their effectiveness after a while. He was wondering, half
>seriously, if this was just to get people to by more bulbs. Has
>anyone heard of this happening?
>Killingworth, CT USA
>jhimmel at connix.com
>John:I have been designing, building, and marketing Light Traps for
>over 22 years. More importantly, I use the traps that I make as a
>Lepidopterists. As a result, I have researched the fluorescent light
>bulb with some GE engineers at their Neala Park Research Facility a
>number of years ago. Here are some of the things I learned.
>Fluorescent tubes were originally design straight. The
>“shaped” fluorescent tubes were originally design for
>home/household lighting as a space saving, energy efficient and
>effective source of light. When UV Black Lights were developed, the
>pest control industry requested a shaped UV tube for their products.
>Bug Zappers and Insect Collection Traps for pest control is a huge
>market for the light bulb manufacturing industry.
>The effectiveness of bug zappers is an ongoing debate. There have
>been numerous studies and papers, which indicate the ineffectiveness
>of bug zappers, especially on the target insect, Mosquitoes. In
>1999, over 6 million bug zapping devices were sold in North America.
>Virtually all use shaped fluorescent tubes.
>The straight tube emits 99% of the light away from the bulb. Shaped
>tubes emit 20% of more of the light back towards some part of the
>tube. The “blue” bands in UV light are easily distorted.
>Once the light is distorted, it is virtually lost. I visited the GE
>Research Facility in 1985. An engineer tested a straight tube and a
>“U” shaped tube. The straight tube emitted a wider and
>longer light pattern. The “U” shaped tube emitted a
>smaller and extremely compact light pattern with considerable
>distortion. Also, as the shape tube ages with use, more and more of
>the light pattern becomes distorted which reduces effectiveness by
>38% after 900 hours of use. This can vary greatly from tube to tube
>and manufacture to manufacture. The straight tube is also effected
>by use by 1% or less.
>The diameter of the tube also effects the amount of emitted light.
>The reach or the distance the effective UV light travels is
>extremely important in the design of the light traps. Agri-light
>Products produced a 15 Watt light trap for use in buildings housing
>live stock to collect flies and other pest insects that were
>attracted by the livestock. Bug zappers then replaced Argri-light
>traps as a matter of convenience as the Agri-light required
>servicing to remove the flies that were collected and killed. Bug
>zappers require no servicing. The bug zapper was more convenient and
>for a period of time it was widely believed that the flies were no
>longer attracted to the zappers. The “U” shape tubes in
>bug zappers distorted the light and had a serious impact on the
>effectiveness of the UV light and the performance of the device.
>Other chemical type products have since been developed and have
>replaced most bug zappers.
>I originally began with 8 Watt straight tubes, my current standard
>light trap is a 15 Watt straight tube. I also produce a 20 Watt
>straight tube. Neither the 8 Watt nor the 15 Watt can match the
>effectiveness of the 20 Watt.
>Sylvania LTD of UK recently introduce the Quantum tube for use in
>the pest control industry. It has been advertised to be 40% more
>effective than the UV tubes currently available. I am currently
>field testing two 15 Watt Quantum bulbs. The current results
>indicate that they have a greater reach. I intend to visit a lab in
>Pittsburgh, PA late this fall and have them perform a UV light test.
>It is very difficult to determine moth populations with the use of a
>single light or type of light. Especially in urban areas where
>reflected light has a huge impact UV lights. Reflected light from
>urban areas as well as moon light greatly reduce the reach of UV
>light. Moon light can make manmade UV light useless.
>It is my considered opinion that straight tubes are much more
>effective than shaped tubes.
>Leroy C. Koehn
>202 Redding Road
>Georgetown, KY 40324
> For subscription and related information about LEPS-L visit:
Richard A. Worth
Oregon Department of Agriculture
rworth at oda.state.or.us
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