SAFE HANDLING OF
CORROSIVE CHEMICALS
                 

A corrosive chemical is one that:

 
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fits the OSHA definition of corrosive in Appendix A of 29 CFR 1910.1200.   "A chemical that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact."
     
 
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fits the EPA definition of corrosive in 40 CFR 261.22 (has a pH greater than 12 or less than 2.5), or
     
 
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is known or found to be corrosive to living tissue.

The major classes of corrosive chemicals are strong acids and bases, dehydrating agents, and oxidizing agents.  Some chemicals, e.g., sulfuric acid, belong to more than one class.

Inhalation of vapors and mists of these substances can cause severe bronchial irritation.  These chemicals erode the skin and the respiratory epithelium and are particularly damaging to the eyes.

Strong acids: All concentrated strong acids can damage the eyes and skin.  Nitric, chromic, and hydrofluoric acids are especially damaging due to the types of burns they cause.  Hydrofluoric acid produces slow-healing, painful burns, and should only be used after familiarization of recommended handling procedures.
   
Strong bases: A few common strong bases are potassium hydroxide, sodium hydroxide, and ammonia.  Ammonia is a severe bronchial irritant and should always be used in a well-ventilated area.  The metal hydroxides are extremely damaging to the eyes.
   
Dehydrating agents: The strong dehydrating agents include concentrated sulfuric acid, sodium hydroxide, phosphorus pentoxide, and calcium oxide.  Because extreme heat is evolved when you mix these substances with water, mixing should always be done by adding the agent to the water to avoid a violent reaction and spattering.  Because of their affinity for water, these substances cause severe burns on contact with skin.
   
Oxidizing agents: In addition to their corrosive properties, powerful oxidizing agents such as perchloric and chromic acids, present fire and explosion hazards on contact with organic compounds and other oxidizable substances.  The hazards associated with the use of perchloric acid are especially severe.  It should be handled only after thorough familiarization with recommended procedures.  (When heating perchloric acid (i.e., digestions) a perchloric acid fume hood equipped with wash down facilities must be used).  Contact the EHRS Department for fume hood requirements.
   
  Keep oxidizers segregated from all other chemicals in the laboratory.   Minimize the quantities of strong oxidizers stored in the laboratory.
   
  Never return excess chemicals to the original container.  Small amounts of impurities may be introduced into the container which may cause a fire or explosion.
   
  Evacuated glassware can implode and eject flying glass, and splattered chemicals.  Vacuum work involving oxidizing chemicals must be conducted in a fume hood, glove box or isolated in an acceptable manner.
   
  Mechanical vacuum pumps must be protected using cold traps, and where appropriate, filtered to prevent particulate release.  The exhaust for the pumps must be vented into an exhaust hood.

Examples of Strong Oxidizers

Ammonium perchlorate Ammonium permanganate
Barium peroxide Bromine
Calcium chlorate Calcium hypochlorite
Chlorine trifluoride Chromium anhydride
Chromic acid Dibenzoyl peroxide
Fluorine Hydrogen peroxide
Iodine Magnesium peroxide
Nitrogen trioxide Perchloric acid
Potassium bromate Potassium chlorate
Potassium peroxide Propyl nitrate
Sodium chlorate Sodium chlorite
Sodium perchlorate Sodium peroxide
Sodium Nitrate  

The following controls and handlling techniques should be used when handling corrosives:

 
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Wear appropriate personal protective clothing, an acid-resistant apron, chemical resistant gloves, and splash goggles/face shield.
 
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Conduct the procedure in a laboratory hood.
 
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Use proper pouring techniques when pouring acids into water.
Always Add Acids to water.
 
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All dilutions of corrosives must be performed in a laboratory hood.

University of the Sciences in Philadelphia • 600 South Forty-third Street • Philadelphia, PA 19104-4495 • phone: 215-596-8800 • email: safety@usp.edu