Some smoke detectors have a provision for a field adjustment of sensitivity and they are required to have an adjustment range of not less than_______?

Some smoke detectors have a provision for a field adjustment of sensitivity and they are required to have an adjustment range of not less than_______?

• A. 0.6% per foot obscuration
• B. 0.4% per foot obscuration
• C. 1.0% per foot obscuration
• D. 0.8% per foot obscuration

Answer: (A)

Field adjustability of smoke-detector sensitivity lets you tailor the detector to the actual environment, so it fires reliably when there’s real smoke but doesn’t nuisance-trip in normal conditions. For field-adjustable devices, there’s a required minimum range for how much you can tune the sensitivity, expressed as percent obscuration per foot. The standard sets this minimum at 0.6% per foot obscuration. That amount gives installers enough flexibility to account for airflow, ductwork, spacing, and aging without making the detector overly sensitive or too easy to ignore. So the correct specification is a minimum range of 0.6% per foot obscuration. Smaller values would limit adjustability and reliability, while larger values are acceptable but exceed the minimum.

Field adjustability of smoke-detector sensitivity lets you tailor the detector to the actual environment, so it fires reliably when there’s real smoke but doesn’t nuisance-trip in normal conditions. For field-adjustable devices, there’s a required minimum range for how much you can tune the sensitivity, expressed as percent obscuration per foot. The standard sets this minimum at 0.6% per foot obscuration. That amount gives installers enough flexibility to account for airflow, ductwork, spacing, and aging without making the detector overly sensitive or too easy to ignore.

So the correct specification is a minimum range of 0.6% per foot obscuration. Smaller values would limit adjustability and reliability, while larger values are acceptable but exceed the minimum.