Sampling microorganisms in suspension in air - by Petri dish appts. incorporating pipe with diaphragm end opening on to Petri dish and fan for circulating air

摘要

An appts. for sampling micro-organisms in suspension in air comprises a pipe one end of which opens on to a Petri dish, and a means of making the air circulate to the Petri dish. The end of the pipe which opens on to the Petri dish is diaphragmed. A stand carries a casing with circular openings in the top and bottom. A vertical pipe is mounted in the opening, of dia. 70 mm diverging to the top of dia. 110 mm where the air enters the appts. The pipe extends to the floor on which it rests by joints. The lowest section converges downwards. The appts. is simple to fabricate and operate. It gives very precise results at least comparable with those given by a gelatin filter appts. and often more sensitive, and giving the nature of the micro-organisms recovered.