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What Hazard Class Do Automotive Batteries Fall Under?


Automotive batteries are a crucial component that allows vehicles like cars and trucks to start their engines and power certain accessories. But besides providing an important function, these batteries can also pose potential hazards if improperly stored, handled, or disposed of. In this article, we will examine specifically which hazard class automotive batteries fall under based on their contents and properties.

Automotive batteries are an example of which hazard class?

Automotive batteries, such as the lead-acid batteries used in cars and other vehicles, fall under the hazard class of corrosive materials.

This is due to the sulfuric acid used as the electrolyte in these batteries.


The primary hazard posed by automotive lead-acid batteries is due to the sulfuric acid electrolyte inside them. Sulfuric acid is extremely corrosive to metals and tissue and is capable of causing severe burns.

Contact with the liquid acid inside automotive batteries can damage equipment or cause injury to the skin and eyes upon exposure. When heated, sulfuric acid can also decompose to release hazardous sulfur oxide fumes.

Other Battery Components

In addition to sulfuric acid, lead-acid batteries contain lead and lead oxide plates, which make up the electrodes. Lead is a toxic heavy metal; however, intact lead battery components do not pose an inhalation or ingestion risk.

The sulfuric acid and lead components together give automotive batteries properties, unlike common flammable, oxidizing, explosive, or other materials. So, by the process of elimination, and due to the main hazard being corrosivity, these batteries fall under the corrosive hazard class.

Classification Systems

There are a few major classification systems that categorize chemicals based on their hazardous properties:

The UN Recommendations classify sulfuric acid solutions at higher concentrations as Class 8 Corrosive Substances.

The U.S. DOT defines sulfuric acid solutions ≥51% concentration as corrosive materials. Lower concentrations (at least 25%) are still regulated as Battery Fluid and acid.

OSHA specifies handling procedures aimed at protecting workers from corrosivity hazards when working with sulfuric acid solutions.

So, by these classification standards, sulfuric acid Electrolytes make automotive lead-acid batteries fall into the hazardous corrosive materials category.

Which hazardous class are automotive batteries an example of?

Automotive batteries, such as the lead-acid batteries used in cars and other vehicles, fall under the hazard class of corrosive materials.

This is due to the sulfuric acid used as the electrolyte in these batteries.

What Hazard Class Do Automotive Batteries Fall Under?

Hierarchy of Controls

When handling automotive batteries, it is important to take appropriate precautions against their corrosivity hazard. The hierarchy of controls concept outlines strategies to contain chemical hazards, ranked from most to least effective:

  • Elimination: Since sulfuric acid is essential for battery function, eliminating it is not an option currently. However, batteries using safer alternative electrolytes could provide an alternative in the future.
  • Engineering controls: Use proper gear like lifting equipment so direct contact with acid inside batteries can be avoided. Storage containers can isolate the hazard.
  • Administrative controls: Establish standard safety operating procedures for handling batteries to minimize risk. Restrict access to battery storage areas only to necessary personnel.
  • PPE: As a last line of defense, wearing appropriate eye and face protection and acid-resistant clothing, gloves, and footwear can protect workers handling batteries from burns.

So, the following controls focused on minimizing contact protecting corrosivity and other battery hazards to humans and the environment.


In summary, automotive lead-acid batteries fall definitively under the hazard class of corrosive materials, specifically due to the concentrated sulfuric acid electrolyte they contain.

Following safety precautions and controls tailored to corrosivity can mitigate the potential hazards batteries pose. Maintaining vigilance about the hazards batteries can present is key to storing, handling, and disposing of them properly. With responsible protocols in place, the risk of unwanted exposure can remain minimal.

Source: Comprehensive Hazard Analysis of Failing Automotive Lithium-Ion Batteries in Overtemperature Experiments

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Ch Ashraf
With over 25 years of electrical contracting experience in the Gilawala area, Ashraf Electric provides reliable and efficient residential, commercial, and light industrial electrical services. As a locally owned company based in Lodhran, we specialize in quickly diagnosing and resolving electrical issues both big and small. Our team of highly skilled electricians is available 24/7 to ensure your electrical systems continue running safely. Whether you require a full rewiring, socket and switch upgrades, safety inspections, or lightning protection systems, contact Ashraf Electric for exceptional customer service and quality electrical workmanship.