Some smoke detectors have a field adjustment of sensitivity and they are required to have an adjustment range not less than what?

Some smoke detectors have a field adjustment of sensitivity and they are required to have an adjustment range not less than what?

• A. 0.3% per foot obscuration
• B. 0.6% per foot obscuration
• C. 1.0% per foot obscuration
• D. 2.0% per foot obscuration

Answer: (C)

Field sensitivity adjustments let you calibrate detectors to respond properly across a range of smoke densities you might encounter in real environments. The specification requires a minimum adjustment range measured as obscuration per foot, so you have enough leeway to tune the detector for different airflow and smoke-generation conditions. The required minimum is 1.0% obscuration per foot. This amount provides enough headroom to compensate for variables like room ventilation, ducting, and burning rates, ensuring reliable alarm performance without being overly sensitive. Smaller ranges such as 0.3% or 0.6% wouldn’t give adequate tuning ability for typical installations, while 2.0% exceeds the minimum but isn’t the mandated lower bound.

Field sensitivity adjustments let you calibrate detectors to respond properly across a range of smoke densities you might encounter in real environments. The specification requires a minimum adjustment range measured as obscuration per foot, so you have enough leeway to tune the detector for different airflow and smoke-generation conditions. The required minimum is 1.0% obscuration per foot. This amount provides enough headroom to compensate for variables like room ventilation, ducting, and burning rates, ensuring reliable alarm performance without being overly sensitive. Smaller ranges such as 0.3% or 0.6% wouldn’t give adequate tuning ability for typical installations, while 2.0% exceeds the minimum but isn’t the mandated lower bound.