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Caustic Substance

What Does Caustic Substance Mean?

Caustic substances are strongly alkaline chemicals. They are corrosive, which means they have the capacity to damage or destroy other substances with which they come into contact through a chemical reaction.

Caustic substances pose dangers to workers in cases of both internal or external exposure, and OSHA requires the appropriate use of hazard communication signage, personal protective equipment (PPE), and other safety measures in order to protect worker safety. According to OSHA, the most common injury resulting from exposure to caustic substances is external burns.

Safeopedia Explains Caustic Substance

A number of caustic chemical substances have occupational uses, and the most widely used is caustic soda, also known as lye or sodium hydroxide (NaOH). Caustic soda has uses in a number of industries, such as paper manufacturing, manufacturing of consumer-grade cleaners and soaps, and textile manufacturing.

The danger of exposure to a caustic substance varies depending on how strongly alkaline the substance is, the stability of the compound it is a part of, and its concentration. Due to their hazardous nature, these substances are subject to hazard communication standards such as the provision of Safety Data Sheets that describe their hazards and display GHS warning signage.

Highly corrosive caustic substances that are recognized as having the capacity to degrade materials must be stored in secondary storage containers (e.g. standards-compliant spill trays) to prevent exposure in the event of a spill. They must also be kept separate from acids, with which strong caustics react violently. Furthermore, the use of proper workplace ventilation equipment is necessary to keep worker exposure at a safe level. Many caustic substances emit fumes, and some caustic substances can degrade metals such as zinc, tin, and lead through a chemical reaction that results in the formation of combustible/explosive gas.

OSHA standards require workers who could potentially be exposed to unsafe levels of chemical substances, including caustic substances, to be provided with proper PPE and respiratory equipment, as well as emergency treatment facilities for responding to potential accidental exposures. The particular safeguards necessary vary depending on the hazards associated with the substance being handled as well as the method by which it is being handled. OSHA’s permissible exposure limits (PELs) provide regulatory exposure limits for various individual caustic substances.

In occupational settings, workers are more likely to face external burns than they are internal injuries. The majority of internal injuries from caustic substances (80%) are experienced by young children who have unknowingly ingested a household cleaner with caustic properties.


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