My girlfriend saved this from being thrown out at the school she teaches at. It’s an amazing insight into how 1979 CEGB thought their work to run coal fired power stations was state of the art environmental protection. The same sites I worked to close & shut down 28 yrs later!
Including the use of gas meter controlled SO2 bubbler monitoring passing captured gas through Drechsel bottles filled with Hydrogen Peroxide. I last used these at Leicester City Council local air quality in 1997.