SIST EN ISO 7779:2019 PDF

Overview

SIST EN ISO 7779:2019 (ISO 7779:2018) - "Acoustics - Measurement of airborne noise emitted by information technology and telecommunications equipment" - specifies standardized procedures for measuring and reporting noise emissions from IT and telecom equipment. The standard defines the A-weighted sound power level as the basic emission quantity for comparing equipment, and supplements this with A-weighted emission sound pressure levels measured at operator and bystander positions. It is intended for type tests, manufacturers and testing laboratories seeking comparable, repeatable noise emission data.

Key technical topics and requirements

• Basic emission quantity: A-weighted sound power level (primary metric for cross-product comparisons).
• Supplementary metric: A-weighted emission sound pressure level at defined operator or bystander positions (useful for identifying annoyance or interference).
• Measurement methods: Three alternative basic noise-emission approaches are permitted:
  • Reverberation test room (ISO 3741) - comparison measurements.
  • Essentially free field over a reflecting plane (ISO 3744, ISO 3745). Any of these can be selected and used exclusively for determining sound power levels.
• Applicable noise types: Broadband, narrow-band, discrete-frequency components, and impulsive noise.
• Discrete tones: Methods to determine prominent discrete tones are given (Annex D).
• Test practices included: installation and operating conditions, microphone positions, measurement surfaces, background-noise correction, calibration, measurement duration and measurement uncertainty estimation.
• Reporting/use: Results suitable for noise emission declaration and product comparison; not intended as installation immission levels but usable for installation planning and statistical production-series values (see ISO 9296).

Practical applications and who uses this standard

• Manufacturers of servers, desktops, printers, telecom racks and other IT/telecom equipment - to produce comparable noise declarations and support product specifications.
• Accredited testing laboratories - to perform type tests that are repeatable and acceptable across markets.
• Acoustical consultants and installation planners - to inform site layout and equipment placement using emission sound pressure data (not a substitute for full immission assessments).
• Regulatory bodies and procurement teams - to specify noise criteria in tenders and conformity statements.
• Quality and R&D teams - to assess design changes, cooling/fan noise mitigation, and production-series variability (statistical reporting per ISO 9296).

Related standards

• ISO 3741, ISO 3744, ISO 3745 - basic noise emission measurement methods (reverberation and free-field).
• ISO 11201 - measurement of sound pressure levels at operator/bystander positions.
• ISO 9296 - noise emission declaration and statistical reporting.
• ECMA TR/27 - guidance for installation planning referenced by the standard.

Keywords: SIST EN ISO 7779:2019, ISO 7779:2018, acoustics, sound power level, A-weighted noise measurement, information technology equipment noise measurement, telecommunications equipment noise.