Downloaded from https://www.everyspec.com MIL-STD-2031(SH) 30.5.1 Acclimation. Animals reeeived from a supplier shall be housed at the testing hdmratoxy for a minimum of 7 days to allow them to become acclimated to the laboratory conditions before being used in testing. 30.5.2 Cm-e. Animal care and maintcnoncc shall be performed in accordance with the procedures outlined in the National lnslitutc of Health’s “Guide for the Care and Use of Laboratory Animals”. The rats shall be housed individually in suspended stainless steel cages and provided with food and water ad Iibitum. Twelve hours of fluorescent lighting per day shall be provided using an automatic timer.
All animals (including (he con[rols) shall be weighed daily from the day of arrival until the cnd of the post-exposure obsetwation period. 30.6 Definitions specific to the procedure. The following definitions are considered important to the performance and understanding of this smoke toxicity screening test: Acute toxicity: Harmful effects leading to lethality from a single short inhalation exposure to the combustion products of materials Mass loading: Amount of material placed in furnace (grams) Mass consumed: Amount of material (grams) depieted in the furnace during combus- tion. This is determined by weighing the charged quartz beaker before and after an experiment. Londed wnun&ration:
Mass loading per unit of exposure chamber volume in milligrams per liter (m#L) consumed Concentmti M- ecmaumed per unit of exposure chamber VoIume (mg/L) LC5P. Concentration that is determined statistically to produce death in 50 pereent of the test animal population exposed for 30 minutes and ohserved for a period of at least 14 days. This value may be calculated based on either mass loaded or mass consumed, as speeified. The lethal effects of the individual and cmmbined four gases for this proecdure oeeurs within 24 houm. E&eme taric potency: A property of smoke where very small amounts of the combusted or therma!ly decomposed material are lethal, i.e., the LCM value is very small.
The value at which smoke exhibits extreme toxicity depends on the fire scenario and should be decided by the eonccmed individuals. 40