Performance Rating of Commercial and Industrial Humidifiers

ARI Standard 640: Performance Rating of Commercial and Industrial Humidifiers

For engineers and designers specifying humidification systems in commercial and industrial environments, understanding equipment performance is paramount. ARI Standard 640 provides the essential framework for evaluating and comparing the capabilities of these critical systems, ensuring reliable and efficient operation. This industry-leading standard is your guide to selecting the right humidifier for demanding applications.

What is ARI Standard 640?

ARI Standard 640, developed by the Air-Conditioning and Refrigeration Institute (ARI), establishes definitive criteria for the performance rating of commercial and industrial humidifiers. Its primary purpose is to provide a consistent and authoritative methodology for testing, classifying, and publishing the performance characteristics of these devices, enabling accurate product selection and comparison.

Scope & Purpose

This comprehensive standard governs the performance evaluation of factory-made commercial and industrial humidifiers. It covers devices that utilize electric, gas, or hot water as energy sources, including those that integrate with central steam boiler systems. The standard defines test requirements, rating criteria, minimum data for published ratings, and conformance conditions. Crucially, it excludes central system humidifiers (covered by ARI Standard 610) and self-contained humidifiers (covered by ARI Standard 620), as well as portable units.

Who Must Comply?

• • Primary audience: HVAC Engineers, Product Designers, Test Engineers, and Standards Developers involved with commercial and industrial humidification.
• • Industries affected: HVAC Manufacturing, Building Automation Systems, Industrial Process Control, and any sector requiring precise humidity control in commercial or industrial settings.
• • Compliance nature: Voluntary, but widely recommended and adopted for ensuring product comparability and market acceptance.
• • Enforcement: Compliance is typically self-declared by manufacturers based on rigorous internal testing and adherence to the standard's protocols. Third-party certification programs may also leverage this standard.

Key Requirements Overview

• • The standard mandates specific test procedures to evaluate humidifier performance under defined rating conditions.
• • Professionals must ensure that published ratings accurately reflect a humidifier's capabilities, including humidification capacity (e.g., lb/h or kg/h).
• • Key provisions include detailed definitions of various humidifier types (e.g., atomizing, direct injection steam, heated tank) to ensure clarity.
• • Manufacturers are required to provide minimum data for published ratings, enabling engineers to make informed design decisions.
• • The standard specifies marking and nameplate data requirements for clear identification and performance information.

Related Standards & References

ARI Standard 640 often works in conjunction with other industry benchmarks. For broader HVAC system considerations, ASHRAE standards on HVAC applications and terminology provide essential context. Additionally, standards related to central system humidifiers (ARI 610) and self-contained units (ARI 620) offer complementary guidance for different humidifier categories. This interconnectedness ensures a holistic approach to HVAC system design and performance.