In a four-gas monitor model QRAE 4-gas, which gas is not monitored?

In a four-gas monitor model QRAE 4-gas, which gas is not monitored?

• A. LEL
• B. O2
• C. H2S
• D. CO2

Answer: (D)

The four-gas monitor is designed to guard against the most common acute workplace hazards: a flammable atmosphere (LEL), variations in oxygen levels (O2), hydrogen sulfide (H2S), and carbon monoxide (CO). Carbon dioxide (CO2) isn’t included in this standard four-gas configuration because it’s not treated as one of the immediate, high-risk gases that this specific monitor is built to detect. If CO2 monitoring is needed, a different setup or detector configured for CO2 would be used, but the QRAE 4-gas is configured for LEL, O2, H2S, and CO.

The four-gas monitor is designed to guard against the most common acute workplace hazards: a flammable atmosphere (LEL), variations in oxygen levels (O2), hydrogen sulfide (H2S), and carbon monoxide (CO). Carbon dioxide (CO2) isn’t included in this standard four-gas configuration because it’s not treated as one of the immediate, high-risk gases that this specific monitor is built to detect. If CO2 monitoring is needed, a different setup or detector configured for CO2 would be used, but the QRAE 4-gas is configured for LEL, O2, H2S, and CO.