Downloaded from https://www.everyspec.com MIL-STD-81OD 19 JULY 1983 Hold the test item in the operating chamber (at 240 to 310C (750 to 81)C’F)c&d 95 ~ 5% .RH) for at least”4 hours immediately before inoculation. ., ., d. Inoculate the test item and tbe cotton fabric chamber control items” with the mixed fungal spore suspension by spraying the suspension on the con- trol items and on and into the teat item(a) (if not permanently or hermetically sealed)”in the’form of a fine mist from-an atomizer”or nebulizer.. Per&.onnel with appropriate knowledge of the test item should be available’to ‘aidin exposing its interior surfaces for inoculation. NOTE:
In spraying the test and’control items with composite spore suspension, take care to cover all external and internal surfaces which are exposed during uae or maintenance. If the surfaces are’nonwetting, spray until drops begin to form on them. ,.. ,:, .. . e. Replace covers of the test items without tightening the fasteners (SO that air can penetrate). ., . . f. Start incubation immediate y following the inoculation. .. ,. II-3.2.2 of the teat Item’ a.
Incubate the teat ite”maunder”a daily cycle ‘of temperature”and humid-” ity conditions consisting of 20 hours at a relative humidity of 95 t 5% and an air temperature of 300 ~ 10C (860 A 2oF) followed by a 4-hour pe’riodin which conditio of 95% (+5%, -O%) relative humidity at 25° A 1oC (77° ~ 2° F) are maintained for at least 2 hours. ‘Upto a total of”2 hours of the 4-hour ‘period will be used for the transitions of temperature and relative humidity. follows: temperature 240 to 310C (75° ’to 880F) and relative humidity above 90%. Temperature and humidity conditions during the transition periods must be aa’ b. Repeat the 24-hour daily cycle for the test duration. c.
After 7 daya, inspect the growth on the control cotton strips to verify that the environmental conditions in the chamber are suitable for growth. At this time, at leaat 90 percent of the part of the surface area of each test strip located at the level of the teat item should be covered by fungi. If it is not, repeat the entire test with the adjustment of the chamber required to produce conditions suitable for growth. Leave the control strips in the chamber for the duration of the test. d. If the cotton atrips show satisfactory fungal growth ‘after7 days, continue the test for the required period from the time of inoculation aa specified in the test plan.
If there is a decrease in fungal growth on the” cotton strips at the end of the teat as compared to the 7-day results, tbe test is ‘invalid. ,= METHOD 508.3 ,: 19 July 1983 508.3-14