Bosch Air 4000, Air Purifier Removes 99.9% of all Pollutants through HEPA13 Air Filter, with Smart Sensor, Auto Mode & Sleep Mode (25 dB (A)), Air Quality Feedback, CADR 300m³/h, up to 62.5 m²

Product Information

We’ve split the products here into three groups, with models suitable for small, mid-sized and larger rooms, and you can jump to each section with the links below.

Key specs – CADR: 280m³/h; Max room size: 35m²; Power settings: 4; Dimensions (WDH): 25 x 25 x 45cm; Weight: 3. The CADR aims to provide an objective measure of the effectiveness of a portable air purifier at dealing with different types of allergens.Just set it in its Auto mode and it will run, continuously adjusting the fan speed, until the air quality stays in the safe green zone for over 30 minutes, at which point the fan will turn off.

There’s also still a lot of discussion about the extent to which many viruses are spread through the air or transmitted through contact with respiratory droplets. levels from a maximum 411 micrograms per square metre to 25 in 135 seconds, bringing it down to double figures in just over a minute. A night mode can also help if you want a quiet setting and dimmer lights while you sleep, although we found this doesn’t always work as well as you’d hope.Clean the air purifier, the particle sensor and the surface of the filter ( Chapter 5 “Cleaning and maintenance”, Page 47). We then run standardised tests, spraying a test aerosol inside a small room for five seconds and using an air quality meter to record particulate levels. At full tilt, it’s as noisy as most rival air purifiers, but in its sleep mode you’d struggle to hear it above ambient sound levels – we measured the output at just 31dBA.