The major European manufacturers of evaporative cooling equipment participate in the Eurovent/Cecomaf WG 9 “Cooling Towers”. The Working Group focuses on the environmental importance of efficient and safe heat rejection systems. Evaporative cooling technology is highly effective in this regard, but there has been some concern about the safety of such systems. Accordingly, the Group has prepared these guidelines on how to keep evaporative cooling systems safe. A more extensive code of good practice is available as Eurovent Document 9/5. This is the English version of the Recommendation.