AS NZS 16900.14:2021 Respiratory protective devices一Methods of test and test equipment Method 14: Measurement of sound pressure level (ISO 16900- 14:2020, MOD).
This document specifies laboratory test methods for measuring the sound pressure level generated by the respiratory protective device (RPD) and by RPD warning devices, measured on a headform to which the RPD is fitted.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
Iso 2768-2, General tolerances — Part 2: Geometrical tolerances for features without individual tolerance indications
ISO 16900-5, Respiratory protective devices — Methods of test and test equipment — Part 5: Breathing machine, metabolic simulator, RPD headforms and torso, tools and verification tools
ISO 16972, Respiratory protective devices — Terms, definitions,graphical symbols and units ofmeasurement
IEC 61260-1, Octave-band and fractional-octave-band filters — Part 1: Specifications
IEC 61672-1, Electroacoustics — Sound level meters — Part 1: Specifications
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 16972 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1
A-weighted equivalent continuous sound pressure level
10 times the logarithm to the base 10 of the ratio of the time average of the square of the A-weighted sound pressure, PA during a stated time interval of duration T (starting at t1 and ending at t2), to the square of the reference value, Po expressed in decibels
4 Prerequisites
The performance standards shall indicate the conditions of the test. This includes the following:
a) the number of RPD specimens;
b) any prior conditioning or testing;
c) the RPD operating conditions;
d) the test duration;
e) any deviations from the method(s).
5 General test requirements
Unless otherwise specified, the values stated in this document are expressed as nominal values. Except for temperature limits, values which are not stated as maxima or minima shall be subject to a tolerance of ±5 %. Unless otherwise specified, the ambient conditions for testing shall be between 16 °C and 32 °C and (50 ± 30) % RH. Any temperature limits specified shall be subject to an accuracy of ±1 °C.
For each of the required measurements performed in accordance with this document, a corresponding estimate of the uncertainty of measurement shall be evaluated. This estimate of uncertainty shall be stated when reporting test results, in order to enable the user of the test report to assess the reliability of the result in accordance with Annex A.AS NZS 16900.14 pdf download.