A building with a large glass atrium would be best served by using what type of detector?

• A. Rate-compensation detector
• B. Light obscuration smoke detector
• C. Light-scattering smoke detector
• D. Rate-of-rise detector

Answer: (A)

In a large glass atrium, the air is often moving vigorously due to convection from sun-heated surfaces. That makes detectors sensitive to airflow and smoke movement rather than just actual fire, leading to nuisance alarms if you use standard types. The detector that handles this situation is one that compensates for air movement. A rate-compensation detector adjusts its sensitivity based on the rate of air flow, so it stays reliable in a space with strong drafts and rising heat, reducing false alarms while still detecting real smoke.

Other options don’t address the airflow issue as effectively. Light obscuration detectors rely on smoke blocking a beam of light and can alarm from dust or drafts; light-scattering detectors depend on how smoke particles scatter light and can also be disturbed by air movement and contamination; rate-of-rise detectors respond to rapid temperature increases and can be triggered by solar heating through the glass, causing false alarms. That’s why the rate-compensation detector is the best fit for a glass atrium.