Downloaded from https://www.everyspec.com MIL-STD-810D 19 ‘July 1983 s. Use a rounded glass rod to gently scrape’the surface growth.from the culture of the test organisms. h. Pour the spore charge into a 125 ml.capped 45 ml’of water and 50 to ’75solid glass beads, 5 mm Erlenmeyer flask containing in diameter. -,:, i. Shake.the flask vigorously to liberate the bodies and to break sporee from”the fruiting the spore clumps. j. Filter the 6 mm layer of glass dispersed fungal spore suspension into a flask through a wool contained in a glass funnel. NOTE: This process should remove large mycelial fragments”and clumps of agar. k. Centrifuge liquid.
the filtered spore suspension and discard the super~atant ,+ !. 1. Resuspend the residue in 50 mi of water and centrifuge. Wash the spores obtained from each of the fungi in this manner three times. . Dilute the final washed residue with mineral-salts solution in such a marine;”that the resultant spore suspension shall contain 1,000,000 t 200,000 spores per milliliter as determined witli‘a counting‘chamber.. n. Repeat this operation for each organism used in the test. Perform a viability check for each organism in accordance with ~ 11-3.~.3a. P. Blend equal volumes of the resultant spore suspension to’obtain the final mixed spore suspension. . NOTE:
The spore suspension may be prepared fresh. If not freshly prepared, it should be heldat 6° ~ 4° C (43° ”~ 7° F) for not more than 7 days. .. . . 11-3.1.3 01 itema. Two types of control’tests are required; Using the’ procedure of II-3.1.3a, verify the viability of the spore suspension and’its preparation. By the prooedure of II-3.1.3b, verify the suitability of the chamber environment. ,,, . a. tv of svore susnem \ , (1) Before preparing the composite spore suspension,’inoculate ~~ potato dextrose agar plates with O.2 to 0.3 ml of the spore suspension of the individual fungal species. Use separate potato dextrose agar plates for each species. sterile of each (2) Distribute the inoculum ,.
over fhe entire surface of the platei (3) Incubate the inoculated (75° ”to 880F~ for 7 to 10 days. potato dextrose agar plate at 24° to 31‘C ,, .....’ ,, s., METHOD”508.3 19 July 1983 508. 3-12