Abstract: An installation for contacting a fluid with a gas is disclosed and comprises an enclosure provided in the lower part of its periphery with at least one gas inlet opening and in its upper part with at least one gas discharge opening. The contact unit is composed of a combustible material, and unit is disposed in the enclosure above the gas inlet opening and is suspended from a framework by hooking means which comprise temperature responsive means adapted to cause release of said hooking means in response to the detection of a predetermined temperature at the most equal to the flame temperature of the contact unit.