Noise pressure from different types of vacuum pumps

There are three types of vacuum pumps: liquid ring vacuum pumps, vane pumps and blowers. When comparing these three types of vacuum pumps, the blowers are the noisiest with a sound pressure of 95 dB(A).

The vane pumps come in second place as the noisiest with a sound pressure of 91 dB(A).

The liquid ring pump is, with no comparison, the most silent vacuum pump type. It has a sound pressure of only 81 dB(A) for operators and 64 dB(A) for surroundings at 7 meters. Making it the suitable choice for urban applications and protection of operator’s health.

Blowers

Sound pressure at 1m distance: 95 dB A
Sound pressure at 7m distance: 78 dB A

Vane pumps

Sound pressure at 1m distance: 91 dB A
Sound pressure at 7m distance: 74 dB A

Liquid ring vacuum pumps

Sound pressure at 1m distance: 81 dB A
Sound pressure at 7m distance: 64 dB A

“A three dB(A) increase is actually a doubling of the sound level”

Sound levels are measured on a logarithmic scale and expressed in decibels (dB). Keeping that in mind when comparing sound pressure levels gives the actual numbers a new meaning.

Sound levels at or below 70 dB(A) are considered safe for our hearing. Avoidance or reduction of noise is crucial for operator safety and health. High noise exposure has severe health impacts.

In a vacuum truck, multiple noise sources contribute to overall sound pressure. Therefore, reducing each source decreases total noise.

Morten Lorenzen

CSO