Standard for Sound Quality Evaluation Procedures for Air-Conditioning and Refrigeration Equipment

Standard 1140: Standard for Sound Quality Evaluation Procedures for Air-Conditioning and Refrigeration Equipment

In the competitive landscape of HVAC and refrigeration, product performance extends beyond thermal efficiency to encompass the auditory experience. Standard 1140 provides engineers and designers with the crucial framework to objectively assess and quantify the sound quality of their equipment, ensuring greater market acceptance and user satisfaction.

What is Standard 1140?

ARI Standard 1140, developed by the Air-Conditioning and Refrigeration Institute (ARI), establishes comprehensive procedures for evaluating the sound quality of air-conditioning and refrigeration equipment. Its primary purpose is to provide a standardized, objective method for measuring and quantifying acoustic performance beyond simple loudness, considering subjective listener perception.

Scope & Purpose

This authoritative standard governs the evaluation of sound quality for factory-made, residential, and commercial air-conditioning units, as well as transport refrigeration equipment. It details methods for acoustic measurements, data analysis, and the calculation of a Sound Quality Indicator (SQI). The standard aims to guide the industry in producing equipment with acceptable acoustic characteristics, focusing on the psychoacoustic response to sound. It does not, however, cover safety standards or installation best practices.

Who Must Comply?

• • Primary audience: Acoustic Engineers, Test Engineers, Product Development Engineers, HVAC Designers, and anyone involved in the acoustic performance of HVAC and refrigeration systems.
• • Industries affected: Air-conditioning manufacturing, Refrigeration equipment manufacturing, Building services, and Product testing laboratories.
• • Compliance nature: Voluntary, but highly recommended for product differentiation and certification.
• • Enforcement: Compliance is typically self-declared by manufacturers seeking to demonstrate superior sound quality or to meet specific market demands.

Key Requirements Overview

• • The standard requires the use of established ARI or ISO sound rating procedures for obtaining foundational acoustic data.
• • Professionals must ensure that sound quality evaluations utilize one-third octave band sound power data.
• • Key provisions include weighting measured sound levels to account for psychoacoustic sensitivity to frequency distribution and the presence of discrete tones.
• • The standard mandates the calculation of a single Sound Quality Indicator (SQI) to represent the overall perceived sound quality.
• • Manufacturers are required to adhere to minimum data requirements for published sound quality values.

Related Standards & References

Standard 1140 often works in conjunction with other ARI and international standards for sound measurement, such as those defining octave and one-third octave band analyses (e.g., ANSI S1.11). Appendix C of this standard itself details the normative procedure for calculating the ARI Sound Quality Indicator, providing a direct reference for implementation. Informative appendices also reference methodologies like the Zwicker loudness model (ISO 532-1975 B), offering further context and comparative analysis tools.