CNSM Safety Training for HF Users

Introduction

HF is different from any other kind of acid.  It is very aggressive physiologically because of the F ion, which seeks to replace the Ca and Mg ions in the body if exposure occurs.  ALWAYS call it HF; NEVER CALL IT HYDROFLUORIC ACID.  If you say “hydrofluoric acid”, people usually hear “hydrochloric acid”, a potentially fatal mistake in an emergency room.  You may not work alone with HF – the buddy system must be used!

Mandatory Safety Precautions

Before you begin working with HF, make sure of the folllowing:

• Another person (buddy) is nearby
• The fume hood is working properly: tinsel flowing inward, sash pulled down to where the arrows meet, hood is not too full
• The emergency eyewash/shower is nearby and is operational (not posted “out of service”)
• The benzalkoniumclhoride solution (necessary for treatment) is in the refrigerator
• The “HF Emergency Info” envelope is taped to the refrigerator
• You know where to go for medical treatment.  Students go to the SHC, but employees go to another site if injured while working as an employee.  Employees currently go to Los Alamitos Medical Center, or to Family Health Care in Long Beach.
• Recall that HF dissolves glass, so work only with plastic containers, pipettes etc.

Hazards of HF

HF burns are usually extremely serious, with significant complications possible due to F toxicity.  HF liquid or vapor is both highly corrosive and toxic due to the F ions which readily penetrate the skin and cause destruction of deep tissues and bone, a process which can continue for days if left untreated. Concentrated HF (liquid or vapor) may cause severe burns; lowering of serum calcium, magnesium, potassium etc. and other metabolic changes; pulmonary edema; life threatening cardiac arrythmias etc.  Even moderate exposures to concentrated HF may lead quickly to death if left untreated; hypocalcemia is a possible risk in all instances of inhalation, ingestion, and whenever skin burns exceed an area of 5 inches by 5 inches.

Hazard According to Concentration

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• Concentrations of 40% or higher produce hazardous vapors
• Concentrations of less than 40% normally do not produce hazardous vapors unless heated
• Concentrations of more than 50% cause immediate severe burning, and throbbing pain
• Concentrations from 20-50% may not produce clinical signs or symptoms (including pain) after skin contact for 1-8 hours
• Concentrations less than 20% may not produce clinical signs or symptoms after skin contact for up to 24 hours.
• Concentrations as low as 2% may cause symptoms if the skin contact time is long enough.

First Aid and Medical Treatment

HF burns require immediate and specialized first aid and medical treatment.  Treatment concentrates on binding the F ion to prevent tissue destruction.  SPEED IS OF THE ESSENCE.  Relief of the throbbing pain of HF burns is an excellent indicator of treatment progress; local anesthetics should be avoided.  Medical help must be obtained as the information below is only a general guide to be used until medical help arrives.  0.13% benzalkonium chloride is recommended as part of the treatment process.  This solution is usually kept in a refrigerator located near your work area; know the location!  Extra benzalkonium chloride solution is kept by the Chemistry Issue Room in MLSC-205 and by the Science Safety Office in PH3-032.

1.  Skin Contact

• Flush with large amounts of cool water for 5 minutes (NOT FIFTEEN) while sending someone to call 911; remove all contaminated clothing
• Immerse the area with 0.13% benzalkonium chloride mixed with ice.  Lift the affected part from the solution as needed to prevent frostbite; the use of ice cubes rather than shaved ice lessens this danger.  If you cannot immerse the area, soak paper towels or similar with the solution and apply; refresh the compress every 2-4 minutes.  Continue for at least two hours, although 4-6 hours of this treatment is usually required for severe burns.  After one hour less ice may be used so that the solution is cool rather than cold.
• 2.5% calcium gluconate may also be used to treat these burns; massage gel into the burn site, reapplying every 15 minutes.  This may be repeated over hours or even days.
• The success of the treatments for severe burns is indicated by pain relief.  If pain recurs upon stopping treatment, the treatment must be continued.  Serious burns usually also require calcium gluconate injections.

2.  Eye Contact

· Flush the eyes for at least 15 minutes with large amounts of water.  Do NOT use benzalkonium chloride, although a sterile 1% calcium gluconate solution may be used if available after five minutes of flushing with water.

3.  Inhalation

· Administer a nebulized solution of 2.5% calcium gluconate.

4.  Ingestion

· Have the victim drink large amounts of water as quickly as possible. Do not induce vomiting. Give several glasses of milk or several ounces of “Maalox”, “Mylanta”, or administer “Tums” etc.

HF Hazardous Waste Collection

Collect your HF liquid waste in a plastic container since HF dissolves glass.  Collect solid waste (e.g. pipettes etc.) in a plastic bag.  Make sure you put the yellow, pre-printed CSULB Hazardous Waste Sticker on the waste bottle or bag.  Fill out the label immediately, and call CNSM Safety x55623 for disposal when needed. Do not let the waste get older than 6 months.  

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