ANORDNING VID KOPIERINGSAPPARAT

In a diazo-type copying apparatus, an improvement to prevent external leakage of gaseous ammonia to the atmosphere. The apparatus comprises a developing chamber, transport means within the chamber, means for introducing ammonia gas to the chamber, a first enclosure enclosing the chamber for sealing it from the atmosphere, a second enclosure containing the first enclosure as well as a perforated vacuum tube for collecting ammonia gases escaping from the first enclosure as well as for scrubbing ammonia gases from developed copies and exhausting the gases either to a liquid ammonia absorbing solution, a filter containing an ammonia absorbing solution, a cartridge containing ammonia absorbing pellets or a catalytic converter thereby preventing the ammonia gases from contaminating the atmosphere.