TL;DR
An occupancy sensor is a switch or fixture-mounted device that turns lighting on when it detects a person — by passive infrared, ultrasonic sound, or both — and off after a set vacancy delay. Energy codes including IECC and California's Title 24 require automatic shutoff controls in many commercial rooms, and vacancy-mode versions, which require a manual on, save the most in homes.
What it means
An occupancy sensor is a switch or fixture-mounted device that turns lighting on when it detects a person — by passive infrared, ultrasonic sound, or both — and off after a set vacancy delay. Energy codes including IECC and California's Title 24 require automatic shutoff controls in many commercial rooms, and vacancy-mode versions, which require a manual on, save the most in homes. Placement matters: a sensor that cannot see around shelving or stalls produces the familiar lights-out-while-occupied complaint.
Where it sits in the glossary
Occupancy sensor is part of the Permits group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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