Conditions of Relative humidity and Temperature for Paper Testing in Australia

Conditions of relative humidity and temperature are compared between North American and Australian cities. The greater extremes of temperature experienced in North America make it necessary to heat factories and dwellings more there, giving rise to lower relative humidities indoors. From a survey of the relevant literature it is shown how these drier indoor conditions contributed in 1941 to the adoption of 73 degrees F. and 50 per cent. R.H. as standards for paper testing. From a review of conditions out of doors in Australian capital cities, the conditions indoors are deduced to be considerably more humid than is the case in North America. Because of this, no change is recommended from the existing Australian standard conditions of 70 degrees F. and 65 per cent. R.H., without first making an exhaustive survey of the conditions under which paper is converted and used in Australia.