A corrosive chemical destroys or damages living tissue by direct contact. Some acids, bases, dehydrating agents, oxidizing agents, and organics are corrosives.
Examples of Corrosives
Examples of acidic corrosives include the following:
- Hydrochloric acid
- Sulfuric acid
Examples of alkaline corrosives include the following:
- Sodium hydroxide (lye)
- Potassium hydroxide
Examples of corrosive dehydrating agents include the following:
- Phosphorous pentoxide
- Calcium oxide
Examples of corrosive oxidizing agents include the following:
- Halogen gases
- Perchloric acid
Examples of organic corrosives include the following:
- Acetic acid
NOTE: Concentrated acids can cause painful burns that are often superficial. Inorganic hydroxides, however, can cause serious damage to skin tissues because a protective protein layer does not form. Even a dilute solution such as sodium or potassium hydroxide can saponify fat and attack skin. At first, skin contact with phenol may not be painful, but the exposed area may turn white due to the severe burn. Systemic poisoning may also result from dermal exposure.
Safe Handling Guidelines for Corrosives
To ensure safe handling of corrosives, the following special handling procedures should be used:
- Always store corrosives properly. Refer to the MSDSs and the Chemical Storage section of this manual for more information.
- Always wear gloves and face and eye protection when working with corrosives. Wear other personal protective equipment, as appropriate.
- To dilute acids, add the acid to the water, not the water to the acid.
- Corrosives, especially inorganic bases (e.g., sodium hydroxide), may be very slippery; handle these chemicals with care and clean any spills, leaks, or dribbles immediately.
- Use a chemical fume hood when handling fuming acids or volatile irritants (e.g., ammonium hydroxide).
- A continuous flow eye wash station should be in every work area where corrosives are present. An emergency shower should also be within 100 feet of the area.
Corrosive Example: Perchloric Acid
Perchloric acid is a corrosive oxidizer that can be dangerously reactive. At elevated temperatures, it is a strong oxidizing agent and a strong dehydrating reagent. Perchloric acid reacts violently with organic materials. When combined with combustible material, heated perchloric acid may cause a fire or explosion. Cold perchloric acid at less than 70% concentration is not a very strong oxidizer, but its oxidizing strength increases significantly at concentrations higher than 70%. Anhydrous perchloric acid (>85%) is very unstable and can decompose spontaneously and violently.
If possible, purchase 60% perchloric acid instead of a more concentrated grade. Always wear gloves and goggles while using perchloric acid. Be thoroughly familiar with the special hazards associated with perchloric acid before using it.
Heated digestions with perchloric acid requires a special fume hood with a wash-down system.