This report is a deliverable from IEA-EBC Annex 78 'Supplementing Ventilation with Gas-phase Air Cleaning, Implementation and Energy Implications'. Annex 78 also looked at a new test method for gas-phase air cleaning technologies, how gas-phase air cleaning technologies may partly substitute for outside air, the energy impact of using air cleaners to improve indoor air quality and the long-term performance of gas-phase air cleaners.

This report presents a comprehensive review of the performance of portable gas-phase air cleaning technologies used in non-industrial indoor environments. The study evaluates the effectiveness, limitations, and applicability of various technologies, including adsorbent-based filtration (e.g., activated carbon and chemisorbents), photocatalytic oxidation (PCO), air ion generators, ozone generators, and plant-based biofiltration systems. Performance indicators such as clean air delivery rate (CADR), single-pass removal efficiency, and VOC decay rates are critically assessed. 

The review integrates findings from both experimental and modelling studies to identify key factors influencing device performance, such as airflow characteristics, pollutant types, environmental conditions, and maintenance requirements. Emerging innovations, including thermally regenerable filters and hybrid systems, are also discussed. The analysis highlights that while several technologies demonstrate promising pollutant removal capabilities under controlled conditions, long-term performance, energy use, by-product formation (e.g., ozone), and practical deployment challenges remain significant. The report underscores the need for standardised testing protocols and comprehensive field studies to validate the real-world effectiveness of portable gas-phase air cleaners. This work contributes essential knowledge to Annex 78, supporting informed decision-making for improved indoor air quality management.