Acoustic Terminology 'Cheat Sheet'

Acoustic Survey

A survey of sound levels at one or more locations over a finite time period, using noise monitoring equipment. Customers and local authorities will sometimes use this phrase interchangeably with 'acoustic assessment' to imply an actual evaluation of noise, whereas (strictly speaking) this term refers to the monitoring element alone.

Airborne Sound

Sound travelling through the air. Most of the sounds and noises we deal with in day-to-life fall into this category.

BS 4142

A British Standard which describes how to rate and assess industrial or commercial sound, for example the sound of a factory affecting nearby residents. A common type of assessment required within the planning system. Find out more here.

BS 8233

A British Standard which sets out guidance on reducing noise levels in buildings. A common type of assessment required within the planning system, especially for residential homes exposed to road, rail or air traffic.

Building Regulations Part E

Or 'Approved Document E'. The section of the Building Regulations which tells us how to design and build houses and flats in a way that controls sound transfer. Includes targets which need to be complied with by carrying out tests on the building (see 'sound test').

Control of Noise at Work Regulations 2005

Legislation covering the responsibilities of employers and employees to minimise the risk of hearing loss from excessive noise in the workplace.

Environmental Noise

Described by the EU as "unwanted or harmful outdoor sound created by human activities, including noise emitted by means of transport, road traffic, rail traffic, air traffic, and from sites of industrial activity".

Groundborne Sound

Sound travelling through the ground, usually caused by a vibrating object in contact with the ground such as construction machinery. Ground-borne sound can sometimes make its way into buildings where it becomes airborne sound that can be heard.

Impact Sound

Sound caused by footfall on a floor inside a building, heard by people below or in adjacent rooms.

Noise Assessment

Also known as Noise Impact Assessment. An assessment designed to evaluate the effects of noise on either an existing receptor or a future receptor. Normally carried out when there is the introduction of a new noise source into an area where people are sensitive to noise, or the introduction of new noise-sensitive receptors (e.g. a housing development) in an area exposed to existing noise.

Occupational Noise Survey

A survey of workplace noise levels, to measure the noise levels which employees are exposed to as they go about their work. Used to assess compliance with the Control of Noise at Work Regulations 2005.

Sound Modelling

(Or Acoustic Modelling / Noise Modelling). Use of a computerised set of calculations to predict sound levels at one or more locations. Either proprietary software packages or spread-sheet based models are used.

Soundproofing

A slightly vague term, but we take this to mean insulating a room or whole building with the aim of preventing sound from breaking out into the environment or into other rooms or buildings.

Sound Test

Although sometimes used to describe any type of acoustic measurement, acoustic consultants recognise this phrase specifically as sound testing between adjoining rooms, normally in connection with Part E of the Building Regulations.

Sound Level Meter (SLM)

Sometimes called noise meter or noise monitor. A device for measuring the sound pressure level in the air.

Structure-borne Sound 

Sound which is transmitted along a physical structure. Usually occurs when there is a physical contact between an impact-generating source like footfall or where a vibrating source is in contact with the structure.

Vibration

The mechanical oscillations of particles about an equilibrium point. In others words, particles rapidly moving back and forth. Normally this term in used to refer to vibration in solids such as the ground. Technically though, sound travelling through they air can also be described as a vibration of air particles.