W&H S-11 L G Instructions For Use Manual page 12

Zone M is defined as a »medical environment« and constitutes the part of a room in which potentially
explosive atmospheres may form due to the use of anaesthetics or medical antiseptics and antibacterial
soaps; such atmospheres are typically localized and temporary.
Zone M comprises a truncated pyramid below the operating table which is tilted outwards at a 30° angle.
Zone G, also known as an »enclosed medical gas system«, does not necessarily include areas enclosed
around all sides, in which explosive mixtures are continuously or temporarily generated, directed or used
in small quantities.
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