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The first question you want to ask yourself when purchasing a blacklight flashlight is, “Do you really want to know?” These neat little gadgets employ ultraviolet light to make substances containing phosphors glow in the dark, so you can find out whether or not the carpet in your new apartment has been properly cleaned, if there’s evidence of bed bugs in a hotel room, or spot counterfeit cash. Enjoy these tips on what they can do (make sneaky scorpions gleam blue-green) and what they can’t (remove said scorpions from your shoes), and even have some fun discovering a hidden world.



If you’re training a puppy or have an elderly dog prone to accidents, you aren’t always going to be there with cleaning supplies when a mishap occurs. When you scan your carpet with a blacklight flashlight, patches you’ve missed will emit fluorescent light, allowing you to deep clean problem areas more easily. A smaller flashlight will help you look into smaller corners and spaces under furniture.



To optimize the power of your blacklight flashlight, always be sure your surroundings are as dark as possible. If you live in a city or have a streetlight just outside your living room window, make sure the shades are closed, and consider blocking any cracks of light from under your door with a towel. Results may be harder to distinguish on darker rugs or carpet, but if you’ve committed to using blacklight to attack messes, you can keep light-colored carpet looking fresh and new.



While most people probably purchase a blacklight flashlight for cleanup purposes, the fluorescent world is not a total horror show. Antique collectors can use them to recognize uranium glass, and geologists can check out fluorescent minerals. Just be sure to follow the safety instructions for your light to protect your eyes and minimize your exposure to radiation.