7-43. Which, if any, of the following fire-fighting agents is authorized for use on LOX enriched fires? 1. Soda acid 2. Methyl bromide 3. Carbon tetrachloride 4. None of the above Learning Objectives: Recognize contamination control procedures for oxygen equipment to include detection, purging, and purging equipment. 7-44. How often must an odor test be performed on a LOX trailer when it is not in use? 1. Every day 2. Every 3 days 3. Every 6 days 4. Every 9 days 7-45. How often must an odor test be performed on an aircraft oxygen system? 1. When painting has been performed on the aircraft 2. When odors are reported by the pilot or aircrew 3. When the aircraft oxygen system is found to have a leak 4. When a phase inspection is performed 7-46. How many milliliters of LOX is used to perform an odor test? 1. 100 2. 200 3. 300 4. 400 7-47. During an odor test, odors will be most prevalent under which of the following conditions? 1. While liquid is in the beaker 2. Fifteen to twenty minutes after the liquid has evaporated 3. Both 1 and 2 above 4. When the beaker has warmed to nearly room temperature 7-40. 7-49. 7-50. If odors are discovered during an odor test, what procedure must be performed on the converter or LOX system? 1. It must be refilled and retested. 2. It must be sampled and tested by NADEF 3. It must be purged in accordance with existing directives 4. It must be wet cleaned and refilled What is the most dangerous contaminant of LOX? 1. Water vapor 2. Nitrogen 3. Hydrocarbons 4. Inert solids Which of the following is NOT a psychological effect of hydro- carbon contamination in LOX? 1. Uneasiness 2. Apprehension 3. Panic 4. Asphyxia 7-51. Which of the following is NOT a physiological effect of hydro- carbon contamination in LOX? 1. Panic 2. Nausea 3. Illness 4. Intoxication 7-52. Acetylene is the most hazardous hydrocarbon contaminant in LOX because of its ability to cause which of the following conditions? 1. Freezing of the lines 2. Internal corrosion of oxygen regulators 3. Both 1 and 2 above 4. It becomes its own source of ignition 7-53. Which of the following LOX contaminants will cause mechanical malfunctions of LOX system components? 1. Water vapor 2. Fibers 3. Nitrous oxide 4. Halogenated compounds 49