Class 1 sound level meter
The gold-standard measuring instrument for sound — accurate enough to stand up in an environmental noise dispute.
What it is
About Class 1 sound level meter
A Class 1 sound level meter is precision measurement hardware meeting the IEC 61672-1 Class 1 accuracy specification, used for environmental noise assessments, occupational noise exposure measurement and building acoustics testing where measurement accuracy needs to withstand regulatory or legal scrutiny. Class 1 meters (as opposed to lower-cost Class 2) have tighter tolerances and wider frequency and dynamic range, and require periodic calibration against a traceable reference. Common manufacturers include Brüel & Kjær, Norsonic, Rion and NTi Audio.
What you can do with it
Capabilities
Measure sound pressure levels (dB) to legally and regulatory-defensible accuracy
Log noise levels over time for environmental noise assessments
Perform frequency (octave and third-octave) band analysis of a noise source
Measure occupational noise exposure for health and safety compliance
Conduct building acoustics tests (sound insulation, reverberation time) alongside supporting software
How to learn it
Learning Resources
Institute of Acoustics (IOA) diploma and short courses on acoustic measurement
Manufacturer training (Brüel & Kjær, Norsonic, NTi Audio all run instrument-specific courses)
IEC 61672 and relevant British and ISO standards documentation
Supervised, hands-on measurement practice under a qualified acoustician (standard route into the profession)
Pro Tip
Always log the acoustic calibrator check (before and after each measurement session) alongside your readings — an uncalibrated or drifted meter reading is inadmissible in most environmental noise assessments regardless of how careful your measurement technique was.
Skills that use this tool
Roles that use this tool