Grease or kitchen extract ductwork is normally comprised of steel, normally galvanised sheet steel in an oblong or spiral-wound round structure, but will also be made from all-welded ‘black iron’ or stainless-steel. Separators in electrically charged separator banks, fitted to minimise procedure atmospheric discharge, call for normal cleansing or ‘laundering’ https://fiireresistingductwork01223.articlesblogger.com/52079280/helping-the-others-realize-the-advantages-of-kitchen-extract-systems