1. BS ISO 22197-4. Fine ceramics (advanced ceramics, advanced technical ceramics). Test method for air-purification performance of semiconducting photocatalytic materials. Part 4. Removal of formaldehyde (5th January 2021) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (17 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗