Amirhossein Montazeri

Generator installations are important sources of environmental noise in and around buildings, often exceeding acceptable levels for residential and occupational settings. This systematic review and meta-analysis synthesized quantitative evidence on noise-control strategies for generator systems. Searches of 11 scientific databases to December 2024 identified experimental and field studies reporting measurable noise-reduction outcomes. Twenty-four studies met the inclusion criteria and were pooled using random-effects models. Across all methods—including structural modifications, multilayer acoustic enclosures, silencers, passive materials, vibration isolation, and active or hybrid active–passive noise control—the overall mean reduction was 14.66 dB (95% CI: 12.49–16.83 dB), with substantial heterogeneity. Subgroup analyses indicated superior performance for high-efficiency silencers and well-designed enclosures compared with simple barriers or single-layer treatments. These findings provide consolidated evidence to inform the design and optimization of generator noise-control solutions within the built environment.