CO2 monitoring in offices under Part F 2021: what is required and how to do it well
What Approved Document F actually asks for in offices, where the size exemptions catch people out, and how to specify CO2 monitoring so the reading gets used.
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Knowledge
Quick calculators for selection and site checks, plus our articles and technical write-ups to read and download.
Calculators and tools
Type in your figures and the results update as you go. Use the switch to work in m³/s or l/s.
Please check all figures before using. BOV & Systemair cannot be held accountable for the validity of these calculators. Airflow, duct, fan, heating, acoustic and electrical calculators are derived from an original worksheet by Bob Sproston, 2001, and checked against the Systemair Technical Handbook (2019). E&OE.
Technical resources
Reference material from the manufacturers we work with.
Articles and write-ups
Our weekly LinkedIn articles on ventilation and HVAC, and longer technical notes you can download as PDFs.
Weather louvre selection: free area, face velocity, pressure drop and rain-defence class
Why percentage free area is the wrong number to size a louvre on, what BS EN 13030 rain and airflow classes tell you, and how undersized louvres eat into your SFP.
SFP explained: Part L limits vs ErP SFPint, and where projects lose marks
The data sheet SFPint and the Part L system SFP measure different things. What each covers, where the pressure budget goes, and the checks before an AHU selection is signed off.
Thermal wheel vs counterflow vs run-around coil: choosing AHU heat recovery on commercial merit
Each type can be the right answer and each can be an expensive mistake. A commercial comparison of capital cost, running cost, space, risk and maintenance.