Industrial & Special Hazard Protection

What's the difference between HSSD and a regular VESDA aspirating system?

Standard aspirating smoke detection (VESDA VLF/VLP class) targets sensitivity in the 0.03–0.5 %obs/ft range — plenty for a clean office or general warehouse. HSSD — high-sensitivity smoke detection, typically VESDA-E VLI with a cumulative filter — runs at 0.0015–0.03 %obs/ft and is required by FM Global and most insurers in active data center white space, semiconductor fabs, and telecom switching halls where the equipment value justifies very-early warning.

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