What is the best instrument for establishing...

🔍 Key Concepts

• Confined space hazards often involve BOTH lack of oxygen and presence of flammable vapors • A single‑purpose indicator only tells you about one type of hazard (oxygen OR combustible gas) • Safe hot work usually requires checking for explosive range and adequate oxygen range before entering

💭 Think About

• Which option, by its name, can detect more than one critical hazard at the same time in a confined space? • Before welding, do you only need to know about oxygen level, or also about the presence of flammable gases and vapors? • If you choose an instrument that measures just oxygen OR just combustible gas, what important information might you still be missing?

✅ Before You Answer

• Verify which choice can measure both oxygen content and combustible gas concentration • Check that the instrument can indicate whether the atmosphere is within a safe oxygen range (not too low, not too high) • Confirm that the instrument helps determine if conditions are below the lower explosive limit (LEL) for flammable gases before welding

What is the best instrument for establishing a safe working area before welding in a confined space?

A flame safety lamp

A combination combustible gas and oxygen indicator

An oxygen indicator

A combustible gas indicator

🔍 Key Concepts

💭 Think About

✅ Before You Answer