CRITERIA FOR LABORATORY ACCREDITATION IN THE FIELD OF ACOUSTICS, ULTRASOUND AND VIBRATION METROLOGY

Transcription

1 CRITERIA FOR LABORATORY ACCREDITATION IN THE FIELD OF ACOUSTICS, ULTRASOUND AND VIBRATION METROLOGY Approved By: Chief Executive Officer: Ron Josias Executive - Accreditation: Mpho Phaloane Revised By: STC members Date of Approval: Date of Implementation: SANAS Page 1 of 5

2 CONTENTS: 1. Purpose and Scope Definitions and References Environmental Requirements Technical Requirements... 3 ADDENDUM 1: Amendment Record... 5 SANAS Page 2 of 5

3 1. Purpose and Scope The purpose of this document is to define the specific technical requirements, as agreed to by the Specialist Technical Committee (STC), to be met by accredited calibration laboratories in the field of Acoustics, Ultrasound and Vibration metrology. This document is applicable to all accredited bodies as defined in Act 19 of 2006: Accreditation for Conformity Assessment, Calibration and Good Laboratory Practice Act, Definitions and References SANAS PM SANAS A 01 SANAS Policy Manual References, Acronyms and Definitions accredited body means an organisation or facility that has been accredited by SANAS or by a member of the recognition arrangements of the International Laboratory Accreditation Co-operation (ILAC) or the International Accreditation Forum (IAF); [Act 19:2006] 3. Environmental Requirements 3.1 An accredited laboratory working in the field of acoustics and vibration measurements must be maintained at a temperature of 23 C ± 3 C and any temperature fluctuations must occur at a rate of less than 2 C per hour. 3.2 The relative humidity must be maintained between 30 %rh and 75 %rh. 3.3 The laboratory shall ensure that any background noise and vibration levels are sufficiently attenuated such that they have no adverse effect on the measurements and calibrations performed in the laboratory. 3.4 The environmental conditions specified in the relevant IEC and ISO standards will take precedence over these conditions where calibrations are performed in accordance with these standards. 4. Technical Requirements The following standards include descriptions of the methods preferred for the calibration of the devices as listed below: 4.1 Measurement microphones IEC : 2000 IEC : 2009 IEC : 1995 IEC : 2001 IEC : 2004 Specifications for laboratory standard microphones Primary method for pressure calibration of laboratory standard microphones by the reciprocity technique Specifications for working standard microphones Methods for pressure calibration of working standard microphones by comparison Electrostatic actuators for determination of frequency response 4.2 Sound calibrators IEC 942: 1988, IEC 60942: 1997 IEC 60942: Sound intensity IEC 61043: 1993 Instruments for the measurement of sound intensity Measurements with pairs of pressure sensing microphones SANAS Page 3 of 5

4 4.4 Octave and fractional octave band filters IEC 225: 1966 IEC 61260: 1995 IEC 61260: 2014 Part 1: Octave-band and fractional-octave-band filters Specifications 4.5 Sound level meters IEC 60651: 2001 Renumbering of IEC 651: 1979 IEC 60804: 2000 Renumbering of IEC 804: 1985 SANS 656: 2008 / IEC (60)651 Sound level meters SANS 658: 2008 / IEC (60)804 Integrating-averaging sound level meters IEC 61672: 2003 / IEC 61672: 2013 Part 1 Specifications IEC 61672: 2003 / IEC 61672: 2013 Part 2 Pattern evaluation tests IEC 61672: 2006 / IEC 61672: 2013 Part 3 Periodic tests 4.6 Personal Sound exposure meters (noise dosimeters) IEC 61252: 1993 Specifications for personal sound exposure meters 4.7 Methods for the calibration of vibration and shock transducers Vibration etc. ISO ISO ISO ISO ISO ISO ISO Basic concepts Primary vibration calibration by laser interferometry Vibration calibration by comparison to a reference transducer. Primary shock calibration using laser interferometry Shock calibration by comparison to a reference transducer Calibration of laser vibrometers Calibration by Earth's gravitation SANAS Page 4 of 5

5 ADDENDUM 1: Amendment Record Proposed By: Section Change AM Section 1 Added Reference to accredited body AM Section 2 Added Definition of accredited body from Accreditation Act, Act 19 STC Section 3.1 Environmental temperature limits revised to 23 C ± 3 C STC Section 3.2 Humidity limits revised to 30 %rh and 75 %rh. STC Section 3.3 Revised requirement to record background noise and vibration. STC 3.4 & 3.5 Previous requirement deleted. STC 3.4 New requirement added. STC Section 4 Added technical requirements including list of preferred standards for calibration of measuring instruments in AUV metrology. SANAS Page 5 of 5