Evaluation of a Field Leakage Measurement Method for Building Air-Supply and Smoke-Exhaust Dampers and Comparison with Laboratory Testing

This study established and preliminarily evaluated a portable field leakage measurement method for air-supply/smoke-exhaust dampers. Three brands of general dampers and three brands of airtight dampers, one specimen per brand, were tested on both sides; airtight dampers were also compared with laboratory measurements. Leakage increased with differential pressure, and general-damper results followed a power law. At the same differential pressure, all 234 comparable field points showed greater smoke-exhaust-side leakage. At 25 Pa, all general dampers exceeded the study-specific 25 m3/h screening value, whereas airtight-damper instrument readings were below it; because these values were below the directly calibrated flow range, they were used only for trend characterization and preliminary screening. Below 400 Pa, field and laboratory results showed similar trends without implying metrological equivalence. The leakage rates per unit area of nominal Class 1 airtight dampers fell within the AMCA Publication 511-21 Class 3 range at 250 Pa and the UL 555S Class III range at 1100 Pa. For products of the same size and configuration, the smoke-exhaust side may provide a more conservative screening direction. Given the limited sample size, insufficient low-flow calibration evidence, and incomplete environmental records, broader validation is required; these comparisons do not replace formal certification tests.