May 23, 1989

The purpose of this bulletin is to alert field personnel to a potential serious hazard arising with the use of open containers to hand carry/transport corrosive chemicals. Just recently the Boston Regional Office brought to our attention a fatality involving an employee of a small metals testing firm. The employee was engaged in increasing the percent acid concentration of a 40 gallon acid etch tank that contained a mixture of both nitric and hydrofluoric acids. The employee dispensed via hand pump, approximately 10 liters (2.6 gallons) of 70% hydrofluoric acid into a 15 liter open pail. While transporting this acid the employee either stumbled or lost his balance and splashed his upper torso with the concentrated acid.

According to available reports the company attempted to immediately render first aid to the employee, in that, the employee was deluged with water and immersed in a water rinse tank. The employee, however, died within one hour as a result of acute inhalation of hydrofluoric acid vapors. At the time of the accident the employee was only wearing rubber gauntlet gloves for personal protective equipment.

It appears that it is not uncommon that workers transport small quantities of corrosive chemicals in open containers such as pails from a storage area to the point of final use. The above mentioned accident highlights the need for maintaining adequate first aid supplies, using appropriate protective equipment and exercising extreme caution when handling hydrofluoric acid and other corrosive chemicals.

Anhydrous (hydrogen fluoride) or concentrated aqueous hydrofluoric acid causes immediate and serious burns to any part of the body. Dilute solutions are also harmful, although several hours may pass before the hydrofluoric acid penetrates the skin sufficiently to cause redness or a burning sensation. Wearing clothing, including leather shoes and gloves that has adsorbed small amounts of hydrofluoric acid can result In serious delayed effects such as painful, slow-healing skin ulcers.

Inhalation of the gas/vapors of anhydrous and aqueous hydrofluoric acid can cause severe respiratory tract irritation that may be fatal. All contact of the acid with eyes, skin, respiratory system, or digestive system must be avoided by using personal protective equipment such as face shields, tight-fitting chemical goggles, aprons, boots, coats, jackets, neoprene or polyvinyl chloride gloves, and respirators when appropriate. The protective equipment should be washed after each use to remove any hydrofluoric acid on it. Safety showers and eyewash fountains should be nearby.

Anyone working with anhydrous or aqueous hydrofluoric acid should have received prior instruction about its hazards and in proper protective measures and should know the recommended procedure for treatment in the event of exposure.

Unlike hydrochloric acid or sulfuric acid, hydrofluoric acid has a latent period. In concentrations greater than 50%, the burn in felt immediately and tissue destruction is rapidly apparent; In concentrations of 20-50%, the burn becomes apparent 1-8 hours following the exposure; and in concentrations of less than 20%, the pain and erythema can be latent for as long as 24 hours after the exposure. Latent symptoms can seriously delay proper treatment.

First aid facilities specific to the hazards of hydrofluoric acid must be readily available. Examples of first aid treatment after water flushing (5-15 minutes) are Hyamine 1622 [benzethonium chloride] or Zephiran [benzalkonium chloride] soaks, calcium gluconate gel application or 10- aqueous calcium gluconate injections beneath, around and into the burned area if pain continues after use of the soaks or compresses. Information regarding appropriate first aid treatment is found in the Material Safety Data Sheets.

When transporting anhydrous or aqueous hydrofluoric acid, closed containers must be used. Nonbreakable, corrosion resistant containers (high density polyethylene construction) equipped with spring closing caps that seal tightly, to prevent contents from spilling while transporting, are commercially available. These translucent containers permit easy inspection of content level. Filling and dispensing of liquids should be such that potential spillage is reduced to minimum.

Please distribute this bulletin to all area offices, State Plan States and Consultation project Officers.