THE RUDOLF REPORT

7. ZYKLON B FOR THE KILLING OF HUMAN BEINGS• Humidity and temperature of the air.Needless to say that the Deutsche Institut für Normung (DIN,German Institute for Standardization) has determined the minimumvalues of break-through times of filters under standard testing conditions.These conditions are:• 20°C;• 70 % relative humidity of air;• 30 liters flow-through of air per minute.In Table 15 the values of different filter types are given with theirrespective harmful gas.Hydrogen cyanide filters used by the allies during that time belongedto class 3 with filters to be carried externally. The service life ofsuch filters at hard physical labor and 0.05 vol.% of hydrogen cyanideis given with 3 to 5 hours. At a concentration of over 1 vol.%, the gasquickly breaks through even these devices. 487R. Queisner wrote a report about his experiences with German filterdevices used during the Second World War for delousing procedureswith hydrogen cyanide. 488 The filter inserts “J” and “G” used atthat time were especially developed for being applied in air containinghydrogen cyanide and had a service life of 30 min. with a peak load ofTable 15: Minimum break through times for filtersaccording to DIN 3181 part 1 in minutes 486type test gasbreak through class 1 test class 2 testcriterion (ppm) concentration concentrationA CCl 4 10 80 40 60B Cl 2 1 20 20 30H 2 S 10 40 40 60HCN 10* 25 25 35E SO 2 5 20 20 30K NH 3 25 50 40 60* relating to HCN + (CN) 2class 3 testconcentration486 DIN 3181 part 1, draft, Atemfilter für Atemschutzgeräte. Gas- und Kombinationsfilter derGasfilter-Typen A,B,E und K. Sicherheitstechnische Anforderungen, Prüfung, Kennzeichnung,Beuth Verlag GmbH, Berlin, May 1987.487 War Department, Hydrocyanic-Acid-Gas Mask, US Government Printing Office, Washington1932; War Department, Technical Manual No. 3-205, US Government Printing Office, Washington1941.488 R. Queisner, “Erfahrungen mit Filtereinsätzen und Gasmasken für hochgiftige Gase zurSchädlingsbekämpfung”, Zeitschrift für hygienische Zoologie und Schädlingsbekämpfung,1943, pp. 190-194.231