Acoustic Archive

Acoustic category description

Acoustic Files

File size: 1.39 MB Download

Acoustic design of open-plan offices (NT TR 619)

NT TR 619

  • This application could serve as a practical tool for the acoustic planning of open-plan offices. The acoustic conditions in open-plan offices were investigated in a Nordic cooperation project. Measurements were carried out in five open-plan offices along with a questionnaire to gather the staff’s subjective judgments. A programme for the acoustic measurements was drawn up, specifying how to perform the measurements and which type of parameters to measure.

File size: 2.46 MB Download

Determination in the field of structure-borne sound source strength of building service equipment - A pilot study with inter-laboratory comparisons and a proposal for a Nordtest method (NT TR 616)

NT TR 616

  • A pilot project with an inter-laboratory comparison (round robin) has been performed, where a modified heavy duty washing machine has been circulated for tests among 7 laboratories. The main goal of this pilot project was to find out whether a simple substitution method could be applied to determine the structure-borne sound source strength of typical building service equipments.

File size: 2.57 MB Download

Sound scattering in rooms with ceiling treatment (NT TR 606)

NT TR 606

  • The objective in this project is to present a method for quantifying the diffusing effect of furniture and other equipment in rooms with ceiling treatment. The presence of furniture and equipment in this type of rooms will influence room acoustical parameters such as reverberation time, speech transmission index and sound pressure levels among others. A measure denoted equivalent scattering absorption area is introduced.

File size: 3.64 MB Download

Reproducibility of measurements with ISO 140 and calculations with EN 12354 (NT TR 603)

NT TR 603

  • Uncertainties of measurement and prediction of the sound insulation in a building is an important issue to the building industry, because they put increased expenses on all actors of the building process who have to keep safety margins to prescribed requirements. This report deals with estimates of both types of uncertainty and some recommendations on suitable safety margins are given.

File size: 2.23 MB Download

Inter-laboratory comparison of Nordtest test method for measurement of noise in working environment (NT TR 586)

NT TR 586

  • Nordtest Methods provided in 2002; NT ACOU 114 “Acoustics: Measurement of occupational noise exposure of workers – Survey method” and NT ACOU 115 “Acoustics: Measurement of occupational noise exposure of workers – Engineering method” were tested by making round robin tests in Nordic countries. The methods contain survey and engineering measurements that are based on short-term measurements and splitting up of the working day in work operations with similar noise levels.

File size: 344.79 KB Download

Measurement of drum sound (NT TR 573)

NT TR 573

  • The interest in the effect of background noise on our health and capacity for work has increased. One of the disturbing factors in office spaces, schools etc. is the drum sound, especially when the flooring consists of thin wood parquet or laminate. Drum sound is the noise that appears when an object, e.g. a foot, hits the flooring in the same room as the receiving ear.

File size: 2.14 MB Download

Road traffic - Vehicle noise emission (NT TR 557)

NT TR 557

  • A method for the determination of source parameters for estimation of road vehicle noise has been developed. The main parts of the method have been tested with measurements and this verifies that the method can be used in practice.

File size: 3.68 MB Download

Measurement of Drum Noise - A Pilot Project (NT TR 556)

NT TR 556

  • Drum noise from floors and floorings has been a building acoustics issue for many years although an international standardized measurement method has never been made.

File size: 1.14 MB Download

Whole body vibration in mobile machinery - A pilot study of consequences of new evaluation methods (NT TR 516)

NT TR 516

  • Whole-body vibration emission from mobile workplaces must, in order to meet the EU ‘Machinery Directive’, be declared. A number of methods for the evaluation of whole-body vibration exposure have been standardised. Depending on the choice of evaluation method different conclusions as to the vibration exposure can be reached.

File size: 533.32 KB Download

Determination of work place noise exposure - Consideration of measurements, calculations and uncertainty (NT TR 515)

NT TR 515

  • The aim of the present work is to prepare a Nordtest-method in two parts, namely a simple method for use to safety deputies, persons in industrial or occupational hygiene or in occupational health care etc., and a more advanced method requiring a great deal of competence in acoustics in order to achieve better accuracy in measurement results, if needed.

File size: 701.90 KB Download

Laboratory measurement of sound insulation in the frequency range 50 Hz to 160 Hz – A Nordic intercomparison (NT TR 489 - edition 1)

NT TR 489 - Edition 1

  • Five Nordic laboratories have carried through an intercomparison concerning laboratory measurements of sound insulation at low frequencies. Measurements have been carried out on two different test objects – a sandwich steel plate and a window - in the frequency range 50 Hz to 160 Hz according to ISO/DIS 15186-3, which describes a new test method based on intensity technique.

File size: 710.23 KB Download

Laboratory measurement of sound insulation in the frequency range 50 Hz to 160 Hz – A Nordic intercomparison (NT TR 489)

NT TR 489

  • Five Nordic laboratories have carried through an intercomparison concerning laboratory measurements of sound insulation at low frequencies. Measurements have been carried out on two different test objects – a sandwich steel plate and a window - in the frequency range 50 Hz to 160 Hz according to ISO/DIS 15186-3, which describes a new test method based on intensity technique.

File size: 1.19 MB Download

A simplified method to determine impact sound improvement on light-weight floors (NT TR 488)

NT TR 488

  • It is well known that the impact sound improvement for floor coverings on lightweight floors is very different from that on heavy concrete slabs. Most laboratories have only one test opening and it is expensive to change floors. Thus it would be preferable if it were possible to use a simpler test procedure. In this paper such a procedure is outlined and discussed.

File size: 250.62 KB Download

Performance testing of active noise control (ANC) systems - Guideline (NT TR 487)

NT TR 487

  • This guideline describes a preliminary test method for performance testing of certain active Noise Control (ANC) systems. It sets out requirements for the measurement set-up and representation of the results. The work carried out so far is a first step towards a test method, and this preliminary method can be used as a guideline for testing ANC systems.

File size: 850.65 KB Download

Extended firing sheds and shooting blinds (NT TR 478)

NT TR 478

  • In the period 1996 to 1998 DELTA and the Danish Shooting Association investigated the influence of extended firing sheds and shooting blinds on the noise level in the surroundings. The reason for this was that all Danish shooting ranges had to comply with the noise limits in Guideline 1/1995 from the Danish Environmental Protection Agency, which increased the need for reducing the noise.

File size: 857.24 KB Download

Extended firing sheds and shooting blinds (NT TR 478 - Revised)

NT TR 478

  • In the period 1996 to 1998 DELTA and the Danish Shooting Association investigated the influence of extended firing sheds and shooting blinds on the noise level in the surroundings. The reason for this was that all Danish shooting ranges had to comply with the noise limits in Guideline 1/1995 from the Danish Environmental Protection Agency, which increased the need for reducing the noise.

File size: 305.58 KB Download

System for rating of airborne sound insulation in buildings and of building elements (NT TR 471)

NT TR 471

  • A system is introduced with the purpose of simplifying the basic standard ISO 717-1 for rating of sound insulation in buildings and of building elements. The core idea is that the whole rating procedure can be accomplished by using only two basic weighted sound reduction indices.

File size: 1.20 MB Download

Measurement of Sound Pressure Levels at Low Frequencies in Rooms (NT TR 385)

NT TR 385

  • Comparison of available methods and standards with respect to microphone positions. Proposal for new procedures.

Nordtest

Nordtest is a trademark of Nordic cooperation in conformity assessment. The emphasis of Nordtest is to develop, promote and innovate Nordic test methods and pre-normative activity. Nordtest endeavours to remove technical barriers to trade and promotes the concept: “Approved once, accepted everywhere”.