1. HF safety

2. HF Safety • HYDROFLUORIC ACID IS one of the MOST ACUTELY TOXIC CHEMICALS • There is no concentration of HF which can be relied upon as safe! • As little as 7 ml of anhydrous HF in contact with the skin untreated can bind all the free calcium in an adult • With burns involving greater than 25 square inches significant and sometimes fatal hypocalcaemia can occur • There is no material that is completely resistant to HF degradation Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

3. HF Safety PROPERTIES • Colorless liquid with strong irritating odor • Very strong corrosive inorganic acid • Nonflammable How Is HF Different from other acids? • HF is readily absorbed into skin binding to calcium and magnesium in the body to form insoluble salts that interfere with cellular metabolism causing cellular death and necrosis • Immediate necrosis and pain at high concentrations Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

4. HF Safety EXPOSURE • Liquid exposure (splash) • Gas exposure (lungs, skin & eyes) • Severe burns • Opacification of cornea • Blindness • Coughing/Choking • Cyanosis (blue lips) Worker Airborne Exposure Regulations • Irritation to nose and throat at 3 ppm • Short-term exposure limit 15 min - 2 ppm • 30 ppm is considered immediately dangerous to life and health Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

5. HF Safety SAFE WORK PRACTICES • Never use HF alone • Training • Always Wear Personal Protective Equipment • Documentation & Signs • Always use HF in the lab hood Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

6. HF Safety PPE • Neoprene gloves (Resistant for more than 8 hours) • Saranex coated coveralls • Face shield • Foot protection Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

7. HF Safety EMERGENCY PROCEDURE • Do not panic! Think ThinkThink • Assistant response • Help individual to eyewash/safety shower flush the area with large amounts of water for 5 minutes. Have the person remove all contaminated clothing while under the shower. • DO NOT CONTAMINATE YOURSELF • HF first aid treatment is not limited to washing off the skin (Calcium Gluconate Antidote). Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.