Halloweeen Blacklight Tips

Blacklight Safety

Trace amounts of UV-B are necessary for the production of vitamin D in the skin. Overexposure to UV-B is known to be hazardous, as is just about any UV-C and shorter wavelengths.

We tend to think of UV-A as "safe", but this is only relative.

According to http://hps.org/hpspublications/articles/uv.html

... overexposure to UV-A has been associated with toughening of the skin, suppression of the immune system, and cataract formation. ... The photochemical effects of UV radiation can be exacerbated by chemical agents including birth control pills, tetracycline, sulphathizole, cyclamates, antidepressants, coal tar distillates found in antidandruff shampoos, lime oil, and some cosmetics. Protection from UV is provided by clothing, polycarbonate, glass, acrylics, and plastic diffusers used in office lighting. Sun-blocking lotions offer limited protection against UV exposure.

I consider the eyes to be the most important part of the body to protect from UV. Yes, UV can damage skin, but the eyes are most sensitive, and you only get one set.

Keys to safe use of UV are:

  • ensure correct wavelength of UV
  • Beware high-intensity sources
  • Limit exposure


There a many different materials that react to Halloween Blacklights.
Fluorescent Paint
Just about any paint that is unnaturally bright, or day-glow, will glow under black light.

Invisible black-light paint
"Invisible paint" sounds somewhat like "dehydrated water". Not much to it. But there is such a thing, and it is very useful.

Invisible black-light paint is merely invisible under normal lighting. When the black light hits it, it springs into vibrant color!

Note - Invisible black light paint dries clear, or with a slight milky haze to it, depending on the brand, thickness of applied layer, and color of the black light glow. Some brands look like white paint until the black light hits them. Since these aren't really transparent, I wouldn't consider them to be really "invisible", but they might be sold as such. Ask before you buy.

cheap black-light paints?
Fine quality black-light paints tend to be expensive. Your best bet for making something fluoresce on the cheap is laundry detergent. Many brands of detergents contain "optical brighteners". These are chemicals that pick up the ultraviolet light in the sunlight and fluoresc, making the clothes look brighter. They work even better under black light, giving rise to the infamous "shirt glow" in amusement parks where black light is used

Phosphorescent Paint is commonly called "glow-in-the-dark" paint. It is made from phosphors such as silver-activated zinc sulfide or, more recently, doped strontium aluminate, and typically glows a pale green to greenish blue color. The mechanism for producing light is similar to that of fluorescent paint, but the emission of visible light persists for some time after it has been exposed to light. Phosphorescent paints have a sustained glow which lasts for some minutes or hours after exposure to light, but will eventually fade over time.

This type of paint has been used to mark escape paths in aircraft and for decorative use, such as "stars" applied to walls and ceilings. It is also increasingly used as an alternative to radioluminescent paint.

Laundry Brighteners
RIT-one brand of fabric whitener and brightener which Glows blue-white. Available in liquid or powder form. Essentially, this is pure concentrated optical brightner, and fluoresces a strong blue-white, even in tiny quantities. Under white light, RIT is completely invisible. It is available in powder or liquid form. The powder can be used as-is, for dusting, or mixed with water for a spray.

To use Laundry brighteners to glow your whites in the dark, simply fill a container, such as a plastic tub with enough water to completely cover the items you want to glow. Mix in a box of "RIT Whitener/Brightener" and stir until it is dissolved. Immerse the items into the solution and let them soak for about an hour. Don't rinse it out, simply wring it out and let it dry.

Era-brand laundry detergent
Woolite fabric wash - Glows greenish-white.

Glow in the Dark Spray

"Phosphorescent" material glows in the dark, after exposure to a bright light. It is sometimes called
Glow in the dark(GITD) and often turns up around Halloween. . Black light makes phosphorescent stuff glow vividly!

This spray is a type of water-based paint and will visibly coat the prop or decoration with a pale yellow coating. This coating will glow in the dark the typical greenish-yellow color when exposed to ultraviolet light. Be sure to spray the paint onto the object as evenly as possible.

When sparying any object with Glow in the dark Spray, it is best to Spray under a black light so that you can actually see where the paint is being sprayed, otherwise you may find you ghet the spray on your hands, clothes and other items, making the whole scene a mess.

Glow in the Dark hair Spray

many Glow in the dark hair sprays which come out around halloween time claim that it glows under black light, but many doesn't claim to be phosphorescent.


ink from fluorescent highlighters - Try out just about any bright color. Many of these inks are water-soluable, so you can crack open a highlighter and drop the ink (usually contained in an absorbent felt pad) into fountains, toilet reservoirs, and other areas where glowing water is desired.

Other Blacklight Materials

tonic water - Glows blue due to quinine content. Drinkable!