The explosive range of methane is 5% to 15%...

Question 1 / 270705eccef9ebacbc34ba4d465c8

Question 1 of 270705eccef9ebacbc34ba4d465c8

The explosive range of methane is 5% to 15% by volume in air. This means a vapor/air mixture of __________.

Question 1 of 27070

The explosive range of methane is 5% to 15% by volume in air. This means a vapor/air mixture of __________.

🔍 Key Concepts

• Lower Explosive Limit (LEL) and Upper Explosive Limit (UEL) – what they mean in practical terms • What “too lean to burn” vs. “too rich to burn” means for a gas/air mixture • How a combustible gas indicator is calibrated in relation to %LEL

💭 Think About

• Think about what happens to flammability when the gas concentration is below the LEL and above the UEL. • If methane’s explosive range is 5% to 15%, what does that say about a mixture at 3%, 10%, and 20%? Which side is ‘lean’ and which side is ‘rich’? • . Consider how a combustible gas indicator interprets a reading of 100% LEL – does that mean 100% gas, or the gas concentration that just reaches the lower explosive limit?

✅ Before You Answer

• Verify which concentrations are inside the 5–15% explosive range and which are outside it. • Check the definitions: too lean to burn is on which side of the LEL, and too rich to burn is on which side of the UEL. • Confirm how %LEL is defined: 100% LEL corresponds to what actual gas percentage when the LEL is 5%?

Question 1 of 27070

The explosive range of methane is 5% to 15% by volume in air. This means a vapor/air mixture of __________.

3 percent methane by volume is too rich to burn

5 percent methane by volume will give a reading of 100 percent LEL on a combustible gas indicator

10 percent methane by volume is too rich to burn

20 percent methane by volume is too lean to burn

Question 1 / 270705eccef9ebacbc34ba4d465c8

Question 1 of 270705eccef9ebacbc34ba4d465c8

The explosive range of methane is 5% to 15% by volume in air. This means a vapor/air mixture of __________.

Back

Question 1 of 27070

The explosive range of methane is 5% to 15% by volume in air. This means a vapor/air mixture of __________.