GB/T 17248.2-1999
Acoustics--Noise emitted by machinery and equipment--Measurement of emission sound pressure levels at a work station and at other specified positions--Engineering method in an essentially free field over a reflecting plane (English Version)

Standard No.

GB/T 17248.2-1999

Language

Chinese, Available in English version

Release Date

1999

Published By

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China

Status

Be replaced 2018-12

Replace By

GB/T 17248.2-2018

Latest

GB/T 17248.2-2018

Scope

This standard specifies a method for measuring the emission sound pressure level at work positions and other designated positions near machinery and equipment in an approximately free field above a reflective surface. The working position is the position of the operator, which can be located in the open space of the room where the sound source works, or in the operating room fixedly connected with the sound source, or in a closed space away from the sound source. The designated location may be near the work location, or near unattended machinery. When some of these positions are occupied occasionally or at regular intervals, these positions may serve as spectator positions. The emitted sound pressure level is measured with A-weighting, and C-weighted peak sound pressure level and frequency band sound pressure level can be measured if necessary. Note 1: The contents of this standard and related standards are summarized in Table 1 of GB/T17248.1. This standard specifies the requirements for the test environment and instrument accuracy (engineering level). Corrects for background noise rather than the acoustic environment. This standard also gives specific instructions for the installation and operation of the machine under test, as well as the selection of the working position and other designated positions for microphone placement. The purpose of the measurement is to compare the performance of a given series and different machinery and equipment units under specified environmental conditions and uniform installation and operation conditions. The obtained data can also be used for labeling and verification of emission sound pressure level noise as stipulated in GB/T14574. Note 2: Under any given location and given installation and operating conditions related to a specific machine, the emission sound pressure level measured according to the method of this standard is generally lower than the sound pressure level obtained by direct measurement of the same machine in a typical workshop. Depression, which is due to the effects of reverb and other machinery. Refer to ISO/TR11690-3 for the calculation method of the sound pressure level near a machine operating alone in the workshop. Generally, the difference between the two is 1 ~ 5dB, and the difference is even greater in individual cases. The methods specified in this standard are applicable to all types of machines, mobile and stationary, for indoor or outdoor use. This method is applicable to machines of various sizes and all types of noise defined in GB/T14259 and ISO12001. The type of test environment affects the measurement accuracy of the emitted sound pressure level. This standard requires the test environment to be an approximate free field above a reflective plane (indoor or outdoor). This standard applies to working positions and other designated positions where emission sound pressure levels need to be measured. a) a working position in the vicinity of the machine under test, as is the case with many industrial machines and household appliances; b) a working position in an operating room which is an integral part of the machine under test, as is the case with many trucks and earth-moving machines This is the case; c) a working position in a partially or fully enclosed space (or behind a barrier) which is an integral part of the machine equipment supplied by the manufacturer; d) a partially or fully enclosed working position of the machine under test, This is the case in some large industrial machines; e) a bystander position who is not responsible for operating the machine. f) other designated positions, not necessarily the working position or bystander position; the working position may also be located along the designated path of movement of the operator

GB/T 17248.2-1999 history

• 2018 GB/T 17248.2-2018 Acoustics—Noise emitted by machinery and equipment—Determination of emission sound pressure levels at a work station and at other specified positions in an essentially free field over a reflecting plane with negligible environmental corrections
• 1999 GB/T 17248.2-1999 Acoustics--Noise emitted by machinery and equipment--Measurement of emission sound pressure levels at a work station and at other specified positions--Engineering method in an essentially free field over a reflecting plane

GB/T 17248.2-1999 -All Parts