Sound Level and Noise Measurement FAQs
Lately, our 3M Quest sound level meters have been seeing a lot of action, and are in continued high demand in this early part of 2013. Customers tell me that they're using the meters to re-test working conditions in their plants after machinery or equipment upgrades. When a customer is choosing a sound or noise measurement device, there are two basic questions I hear often:
Do I need a sound level meter or a noise dosimeter? If you're doing basic environmental noise level measurements, trying to locate the source of noise, or evaluating hearing protection equipment for your employees, you'll want to use a portable handheld sound level meter. If you want to know how much noise an employee is exposed to over the course of a work shift or sampling period, you need a personal wearable noise dosimeter. These units usually weigh about 3oz, and are clipped to a worker's hard hat or clothing, close to the ear or "hearing zone".
What's the difference between Type I and Type II sound level meters? There are several basic differences between Type 1 and Type 2 devices, as defined by ANSI Standard S1.4-1971.
| Type I | Type II | |
|---|---|---|
| Application Use | Precision noise measurement | General service measurement |
| Required Overall Accuracy | ±1 dBA | ±2dBA |
| Microphone* | Condenser mic required | Uses either condenser or ceramic mic |
| Frequency response | ±0.5 dB between 22.4 and 11200 Hz | ±0.5 dB between 63 and 2000 Hz |
| Std. Frequency Weighting | A- and C-, plus Linear Response | Generally A- only |
* Condenser microphones are highly sensitive and have a wide dynamic range. Ceramic microphones are more rugged, but less sensitive.
If you've done any upgrading or replacement of machinery or systems in your work environment, and are concerned with the changing noise levels, you may want to run a quick sound level test to make sure you're still in compliance with OSHA and your workers' hearing won't be compromised by additional workplace noise exposure.
RAECO Rents is proud to offer 3M Quest's industry-leading line of sound level meters and noise dosimeters available to rent sound level meters and noise dosimeters. Please don't hesitate to call me for help with your sound level and noise monitoring needs.