UV light will only kill bed bugs if they stay close to it for more than 2 hours at a distance of 0.1 meters. The ultraviolet rays can damage their internal cells and stop them from developing. Bed bugs hate light thus using UV rays is not an effective way of controlling them unless they are trapped.
For UV light to kill bed bugs, you need to expose them to UV-C rays at a close range of 5-10 Centimeters for 2-3 hours. The time it takes to kill adult bed bugs depends on their size and when last they had a blood meal. However, their nymphs will die after 1-2 hours of exposure in an airtight environment.
However, it is only UV light under the C spectrum that kills bed bugs and this only happens if they are exposed to it at a close range for hours. The closer they get, the shorter it takes to eliminate them. Bed bugs cannot stay still under any light and it will be a hustle to use this against them.
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Using UV light to detect bed bugs
UV light can be used to detect bed bugs because they glow when UV rays contact their outer layers. After bed bug eggs have hatched, they produce nymphs that are not easy to detect. UV light rays can also make the nymphs visible thus making it possible to deal with an infestation.
While the nymphs are hard to detect in a bright room, adult bed bugs are equally difficult to notice in a dark room. If you suspect an infestation in a room with poor lighting, using UV light can help in detecting bed bugs. A handheld UV light can be reflected on hidden areas while scanning in order to find them.
Bed bugs glow under UV light because they have phosphorus elements on their back. This will absorb the UV rays and give a reflective light that is visible to the human eyes in the dark. This is why UV light detectors can help in identifying them in a dark room.
You can also see bed bug poop with UV light if you direct the rays at them. After sucking blood, bed bugs will digest the required nutrients and release the waste in a liquid form. This is defecated in a soft non-solid state with a dark brown appearance. It only turns black as it continues to dry up.
How to detect bed bugs with UV light
You need to get a flashlight that is designed to produce UV rays. They are also known as blacklight flashlights and most of them can be held just like any other. Once you have this, you need to identify the suspected hiding areas so that you can shine it in them.
Bed bugs hide in dark areas that are rarely touched by humans or pets. They do not like external activities or light. If you are in the bedroom, check your wardrobe joints, the dark end of drawers, under the bed plus its joints. When scanning your mattress, concentrate on the joints.
Hold the UV flashlight with one hand and use the other to spread and open the joints to clear the way. Shine the light against those areas as you can slowly. In case you spot them, spray them with a homemade combination of Isopropyl alcohol and witch hazel for bed bugs in equal parts. This solution will kill them on contact.
Are bed bugs attracted to UV light
UV light does not attract bed bugs because they are naturally photophobic. This means that they will avoid light as much as possible and this is what keeps them from danger. However, this does not mean that they will not bite you at night if you sleep with the lights on.
Those bugs live in dark areas and hidden cracks in beds, mattresses, furniture, or upholstery. They do not need light to find their host and this is why they can find and bite you in a totally dark room. What attracts them to a host is the carbon dioxide and the natural heat produced from the body.
Secondly, bed bugs are not attracted to UV light because they have high energy that can heat them up very fast. This will repel them after a short time of exposure unless they are in a closed area. The heat will rattle them and they cannot remain in one place that is being struck by ultraviolet rays.
To conclude, there is no form of light that can make bed bugs come out from their hiding areas. Those bugs are smart and this makes it difficult to eliminate them. If you see a bed bug in broad daylight, it is either very hungry or running away from danger.
Does UV light kill bed bug eggs?
Bed bug eggs are extra tiny and in most cases, they look like salt spread on a surface. Some of them can be very tiny. You may only be able to see them with the help of a microscope unless you have very good eyesight.
To get rid of bed bug eggs, place them 10cm from the light source and irradiate them under UV-C rays at 280nm for 2-3 hours. The heat produced from those rays is enough to dry them up. Those eggs at their development stage are still weak and they cannot survive direct UV irradiation at a close range.
The light will destroy the weak egg structures and this will stop them from developing into the next stage. The UV-C rays make the cells extra mobile and the longer they stay under the rays, the more they are likely to die.
Bed bug eggs can also glow under UV light and the rays will also heat up the natural sticky liquid that glues them on a surface. When heated, they drop down and this reduces their survival chances. Bed bug eggs are heat resistant and you need to increase the exposure time if you want to get rid of them with UV light.
This long exposure duration makes those methods less effective and tiresome to use. Using ultraviolet rays for bug control is costly in terms of time and energy spent. It is therefore advisable to only use UV light when detecting bed bugs in dark areas. When it comes to killing them, get control measures that work instantly.