Gases

Gases are materials that exist as individual molecules in the air at room temperature. Gases are measured as a percent volume of air, or parts per million (ppm). One percent volume of air is equal to 10,000 ppm.

Examples of gases found in the construction industry include:

• Gases used for welding and cutting - oxygen and acetylene
• Gases used for heating and fuel - propane and methane
• Naturally occurring gases in sewers - carbon dioxide and hydrogen sulfide
• Gases produced during welding, cutting, and brazing
• Diesel exhaust

Toxic gases can irritate the skin, throat, eyes, or lungs (local health effect), or they may pass from the lungs into the blood stream to damage other parts of the body (systemic health effect).

To learn more about Construction Chemical Hazards visit our Construction Chemical Hazards & Toxic Substances Online Training web page.