Background Noise: Why Is It a Serious Problem?

Part of ALTA Integra's Acoustics 101 lesson series.

Background noise — the continuous ambient sound present at a given location, measured apart from any intermittent noise — is one of the most common problems acoustic consultants are asked to solve, and one of the most underestimated. If you live in a city, you already encounter it constantly: car horns from the street below your office, drilling from nearby road works during your commute, or your neighbor's television bleeding through the wall just as you sit down to relax.

In engineering, the International Electrotechnical Commission (IEC), under IEC 801-21-13, defines noise as any disagreeable or undesired sound or other disturbance. That definition is inherently subjective — which is exactly why acoustic consultants conduct surveys to understand what noise their clients actually want addressed, while also flagging noise that clients may not realize is harming them.

Most noise-control work in a project centers on reducing background noise levels specifically. To see the difference: in an office, the continuous buzzing of HVAC equipment is background noise, while the high-pitched squeal of a photocopier is intermittent noise. People generally tolerate the sound of colleagues talking or walking, but the constant hum in the background is what quietly wears them down. Below are three ways elevated background noise causes real harm.

It Impairs Work Productivity

Numerous studies agree that uncontrolled background noise measurably lowers performance at work. A study by the Buffalo Organization for Social and Technological Innovation (BOSTI) found that 65% of open-office workers surveyed felt distracted by noise.

A separate study by Ising et al. at the German Federal Institute for Occupational Safety and Health found that reducing background noise from 41 dB(A) to 35 dB(A) — dB(A) being the standard unit for sound pressure level — decreased word-processing errors by 52%.

It Harms Our Wellbeing

Occupational hearing impairment from noise has been studied extensively, and many countries regulate permissible noise exposure in the workplace specifically because of it. Masterson et al. found that 23% of American workers exposed to occupational noise experienced hearing loss, compared with only 7% of those who weren't — a significant gap, and one that is mostly preventable through proper acoustic design applied early in a building's life, since most hearing damage from noise exposure is irreversible.

Office workers face a different but still real risk. Published in Noise Health Review in 2003, Babisch et al. showed a correlation between noise and cardiovascular risk. Munzel et al., writing in the European Heart Journal in 2014, elaborated further: noise exposure increases cardiovascular risk factors through mental and physiological stress. According to a review published in the Journal of the American College of Cardiology, noise contributes to an estimated 600 deaths per day in Europe alone.

It Reduces Speech Intelligibility and Sound Quality

Speaking over background noise takes real effort — you typically need to raise your voice roughly four times louder than the ambient level just to be heard clearly, which becomes exhausting in a workplace with sustained high background noise.

In factories, hearing protection such as earplugs or noise-canceling headphones helps prevent hearing damage, but it introduces its own tradeoff: reduced speech intelligibility, which can make warning signals and verbal safety instructions harder to hear. In environments where safety is the priority, the better strategy is to control noise at its source or along its transmission path rather than relying on hearing protection alone.

The same problem shows up in performance venues. Background noise leaking into a concert hall — especially one located near a busy street — can interfere with a performance and lower perceived sound quality, unless the space has been properly treated to keep exterior noise out. Identifying and controlling this kind of background noise is a routine part of ALTA Integra's building acoustics consulting work.

Frequently Asked Questions

What exactly is background noise?
Background noise is any noise that can be heard continuously at a given location and time, measured apart from intermittent noise and other extraneous sound — for example, the constant hum of HVAC equipment in an office.

How is background noise different from intermittent noise?
Background noise is continuous, like HVAC hum. Intermittent noise is occasional and short-lived, like a photocopier's squeal or a passing vehicle.

Can background noise really affect health, not just comfort?
Yes. Research links elevated background noise to reduced work performance, increased cardiovascular risk, and — in occupational settings with high noise exposure — hearing loss.

Why not just use hearing protection to solve noise problems?
Hearing protection can reduce speech intelligibility, which is a serious tradeoff in environments where hearing warning signals or instructions matters for safety. Controlling noise at its source or transmission path is usually the better long-term solution.

What is dB(A), and why does it matter here?
dB(A) is the A-weighted decibel scale, the standard unit for expressing sound pressure level in a way that approximates how the human ear perceives loudness — it's the unit used throughout background noise measurement and regulation.

Suggested internal links: Sound Pressure Level (SPL), Noise Criteria: A Background Noise Rating Standard, Noise Control Performance Indices & Ratings.