Hydrogen Fluoride: The Burn You Don’t Feel Until It’s Too Late
Hydrogen fluoride is a colorless, fuming, sharply pungent chemical that shows up as a gas, as a liquid when anhydrous, or dissolved in water as hydrofluoric acid. It has a well-earned reputation as one of the sneakiest hazards in the business, because it manages to be both an aggressive corrosive and a systemic poison rolled into one deceptively small molecule.
It’s a workhorse of the semiconductor industry, glass etching, refrigerant and fluorochemical manufacturing, refinery alkylation, and metal cleaning. What sets HF apart from your typical acid is the fluoride ion: it slips through skin and deep into tissue, then hunts down the body’s calcium and magnesium, which can trigger dangerously low calcium levels and life-threatening cardiac arrhythmias from exposures that don’t even look that bad on the surface.
The cruelest trick is the delay. Dilute HF can cause little immediate pain, so someone can be seriously exposed and keep working, only to develop deep, throbbing tissue destruction hours later once the fluoride has done its damage underneath. It also reacts with many metals to release flammable hydrogen gas, and it attacks glass and concrete, so ordinary containers and surfaces are no guarantee of safety.
Whether you’re at a chip fab, a refinery, a rust-removal operation, or a transport spill, treat every HF exposure as a medical emergency even when the patient feels fine, and get calcium gluconate into your treatment plan early. Approach upwind in full chemical protection with SCBA, decon aggressively and immediately, keep it away from incompatible metals, and never let a lack of pain convince you or a patient that the exposure was minor.
Have fun and let us know how you did in researching the hazards.
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About the Author:
Dave Donohue is a hazardous materials course developer, educator, and trainer with experience at the local, regional and national level. He is also a Master Exercise Practitioner, firefighter, and emergency manager.
