Hydrofluoric acid (HF) can cause extreme irritation to the nose, throat and respiratory system at low level vapor exposure. Severe exposures to vapors or contact with HF solutions can cause nose and throat burns, lung inflammation and pulmonary edema. HF will also deplete calcium levels in the body if not properly treated, resulting in death due to hypocalcemia.

Due to the extreme toxicity and corrosivity of HF any spill of this material must be cleaned up with great care.

All spills of Hydrofluoric acid will be will be cleaned by the emergency response team. The immediate area of the HF spill must be cleared of all non- response personnel. Depending on the concentration of the HF solution and location of the spill, an EVACUATION must be considered.

Minimum PPE for Hydrofluoric acid response includes:


KAPPLER CPF 2 (or higher) SUITS, with hoods up




Spill response information and special precautions for Hydrofluoric acid:

1) Concentrated HF (70%) solutions may be diluted with water before clean up to reduce hazards. However, the water must be added slowly and carefully to prevent boiling of HF solution due to exothermic reaction of water and HF. Contain spill before adding water to prevent spread of contamination.

2) HF will react with all silicon containing materials such as glass, concrete AND CHEMICAL SPILL SORBENTS SUCH AS VERMICULITE AND MAGICSORB(tm). This reaction will cause the generation of the highly toxic gas, silicon tetrafluoride. Spill responders must be aware and prepared for this possibility.

(A) Using Liquid Neutralizer Methods

The Hydrofluoric acid will be absorbed on polypropylene pads, which will be placed in an appropriate container (5 gal plastic pals or lined drums), secured and then transported to the waste water treatment facility or the hazardous waste yard for treatment or disposal.

The remaining acid residue will be neutralized using a liquid acid neutralizer. The neutralized residue will be absorbed on pads and placed in appropriate containers. This material will be treated as a hazardous waste until determined otherwise.

This neutralization treatment will be done at least three times, after which the contaminated site will be analyzed using pH paper. Additional treatment will continue until all acid residue is neutralized.

Final clean-up will be performed using normal and appropriate maintenance procedures for the contaminated area.

(B) Using Solid Sodium Bicarbonate

Free liquid will be diked and contained with the solid neutralizer. Sufficient material will be spread over the spill to just cover the surface with a light coating. The solid will be thoroughly mixed to effect absorption of all free liquid. If necessary, a small quantity of water may be added to cool the slurry or increase the rate of neutralization. If a color indicator is not present to monitor the pH, then pH paper should be used. The responders should attempt to maintain the final pH in the range of 6 to 10.

After all free liquid is absorbed and the residue is containerized, the area should be rinsed at least twice with water to remove residual contamination and excess solid neutralizer.