ISO 12759-1:2023

Overview - ISO 12759-1:2023 (Fans - Efficiency classification for fans - Part 1)

ISO 12759-1:2023 establishes the general requirements for classifying fan power consumption and efficiency across the ISO 12759 series. Published in 2023, this part defines terms, symbols, installation categories and the scope for efficiency classification. It applies to fans themselves (not the system in which they operate) and excludes air curtains. Detailed procedures for application-specific classifications are provided in Parts 3–6 of the ISO 12759 series.

Key SEO terms: ISO 12759-1, fan efficiency classification, fans efficiency, fan efficiency grade, specific fan power (SFP)

Key technical topics and requirements

• Scope and exclusions: Classification applies to fan performance and power consumption; does not provide methods to compare classifications or establish minimum efficiency limits (MELs).
• Definitions and limits: Includes core definitions (fan, impeller, driven fan, fan without drives/bare shaft) and a physical limit distinguishing fans from turbo‑compressors (work per unit mass normally ≤ 25 kJ/kg - ~30 kPa at a reference density, pressure ratio ≤ 1.30).
• Installation categories (A–E): Standardized test configurations describing inlet/outlet arrangements (free/ducted, with/without partition). These categories are essential for consistent fan efficiency classification.
• Testing & calculation methods: Mandates the use of standardized airways (ISO 5801 referenced) and describes acceptable methods: full‑size testing at declared speed, modified‑speed testing, subscale testing and application of scaling rules. It also covers tolerances, selection of test methods, and calculation requirements.
• Power and efficiency relationships: Defines efficiencies (static vs total), efficiency grades (FEG, FMEG, JFMEG), and provides a power diagram and table relating input powers to efficiencies for different installation categories.
• Informative annexes: Annex A on protective guards, Annex B on fan efficiency, energy effectiveness and specific fan power (SFP), Annex C on performance variation between installation categories.

Keywords: installation category, fan performance testing, ISO 5801, fan efficiency grade, fan motor efficiency grade

Practical applications and who uses this standard

ISO 12759-1 is used by:

• Fan manufacturers for product classification, R&D and performance declaration
• Test laboratories and certification bodies conducting standardized fan tests
• HVAC and industrial engineers specifying fans for ventilation, air‑conditioning, process air, combustion air and pneumatic conveying
• Energy managers, procurement teams and regulators evaluating fan efficiency, energy consumption and specifying efficiency grades for tenders
• Standards developers and policy makers aligning MELs and labeling schemes (note: this part does not set MELs or comparison methods)

Practical benefits: consistent fan efficiency labeling, improved equipment selection, better energy forecasting and comparability of manufacturer declarations when paired with the procedural Parts 3–6.

Related standards

• ISO 5801 (performance testing using standardized airways)
• ISO 13348, ISO 13349-1/2, ISO 13350 (vocabulary, tolerances and jet fan testing)
• ISO 12759 Parts 2–6 (drive/motor considerations and application-specific procedures)
• ANSI/AMCA 230-23 and 260-20 (complementary test methods)

Using ISO 12759-1 helps ensure consistent, internationally‑aligned fan efficiency classification and supports energy‑efficient fan selection and product development.