ISO Established New Air Cleaning Standards
The organization released a classification system for devices used to manage molecular contamination in buildings.
Updated on Sept. 23, 2026 in Asthma
ISO has published a new classification system for gas-phase air cleaning devices used in general ventilation. The document aims to standardize how systems are assessed for their ability to remove molecular contaminants in indoor spaces.
Why it matters
Standardizing these cleaning devices helps building managers and engineers accurately assess indoor air treatment quality. This framework is essential for facilities utilizing partial or full air recirculation to maintain healthy environments.
ISO/AWI 10121-4 establishes a framework using 3 required reference pollutants—ozone, nitrogen dioxide, and toluene—alongside optional formaldehyde and isopropanol. Devices are categorized into 3 distinct duty levels based on their performance range.
The players
ISO
The International Organization for Standardization is a non-governmental entity that develops and publishes voluntary, consensus-based international standards for various industries.
The details
The standard applies to systems using gas-phase air cleaning media for indoor air treatment. Performance is measured against specific chemical contaminants, allowing for consistent assessment of air quality technology across different sectors.
Timeline
September 23, 2026: ISO published the standard document.
The Big Picture
This document extends the foundation set by ISO 10121-1 by creating a classification system tailored for active air cleaning devices. It marks a significant transition from general testing to a structured performance-level assessment for indoor air quality.
Standardized air cleaning systems provide more reliable protection against volatile organic compounds and pollutants that can trigger respiratory issues. Patients with asthma or chemical sensitivities may benefit from facilities that utilize certified devices.
The takeaway
Using standardized equipment ensures that indoor environments meet verified air quality targets. Managers should look for devices that meet these new duty levels to ensure optimal protection for building occupants.
Further reading
Learn more about managing indoor air quality for respiratory health in our Asthma section.
More information
Read the full technical specifications on the ISO standard documentation page.
Source note: This article includes information reported by ISO.
