DIN 45680 specifies procedures for measuring and evaluating low-frequency noise (typically 8 Hz to 160 Hz) immissions in buildings and indoor environments. Low-frequency noise from sources such as wind turbines, industrial equipment, traffic, and HVAC systems can cause annoyance and health effects even at sound pressure levels below conventional noise limits. The standard defines frequency-weighted assessment methods, measurement locations, and evaluation criteria specific to low-frequency phenomena. Accreditation for this test method enables laboratories to conduct specialized assessments required for wind energy projects, industrial operations, and building acoustics investigations in sensitive environments.
What it measures
Sound pressure levels in the low-frequency range (8–160 Hz)
Low-frequency weighted acceleration and vibration metrics
Frequency content and tonal characteristics of low-frequency sources
Indoor sound field distribution and room resonance effects
Renewable energy (wind turbine) development and operationIndustrial noise and vibration controlBuilding acoustics and occupant protectionEnvironmental health and public protectionRegulatory compliance and permit assessment
Related Standards
DIN 45681Acoustics — Tonality assessment
ISO 389-7Acoustics — Reference zero for the calibration of audiometric equipment — Part 7: Reference threshold of hearing under free and diffuse sound field conditions
ISO 226Acoustics — Normal equal-loudness-level contours
Scope