Ontario Office of the Fire Marshal (OFM) Hazmat Awareness and Operations Certification Practice Exam 2026 - Free OFM Hazmat Practice Questions and Study Guide

Question: 1 / 400

What is the lower explosive limit?

The weight of a substance compared to the weight of an equal volume of water.

The percentage of gas or vapour concentration in air.

The minimum temperature at which a liquid gives off vapours.

The minimum concentration at which a vapour forms an ignitable mixture.

The lower explosive limit (LEL) refers to the minimum concentration of a vapor or gas in the air that is needed to create an ignitable mixture. When the concentration of the vapor is below this threshold, it will not ignite, even if there is an ignition source present. This concept is critical in understanding how hazardous materials behave in the environment, especially in fire and explosion prevention strategies.

In the context of hazardous materials and emergency response, recognizing the LEL helps responders assess the potential risks associated with a particular substance. It guides the approach to incidents involving flammable gases or vapors by determining safe distances and necessary precautions. Understanding this limit is crucial for effective incident management and ensuring the safety of emergency personnel and the public.

Get further explanation with Examzify DeepDiveBeta
Next Question

Report this question

Download Ontario Office of the Fire Marshal (OFM) Hazmat Awareness and Operations Certification Practice Exam PDF Study Guide
Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy