fire proof
fiberglass coated
plenum rated
teflon coated
单选题According to the following statement， can you tell me which term is described？（） It is the air return for an air conditioned system. In most buildings， the area above a drop ceiling orunder a raised floor is used as the air return （source of air） for the air conditioning. Those drop ceiling and raised floors are also where wire is often installed. If wire and cable is installed in a dropceiling or raised floor， it is out of sight. If that cable were burning， it would give off toxic fumes.These would be fed to the rest of the building by the air conditioner. As a result， people could beinjured even though they are a long way from the fire.A DAS areaB plenum areaC extended areaD RF special area
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单选题When must a dry chemical fire extinguisher be recharged?（）A After each useB When the air temperature exceeds 90°FC Every 6 monthsD Every 12 months
单选题A Certificate of Inspection issued to a small passenger vessel describes（）.A the mimimum fire extinguishing equipment，lifejackets，survival and rescue craft she must carryB the name of the managing operatorC any special conditions or restrictions on her operationD All the above
单选题Oceangoing dry bulk cargo vessels over 1000 GT must have approved combination-type fire nozzles at all（）.A fire stations aboard the vessel，except for those in open deck areas weatherdeck and cargo hold fire stationsB interior fire stationsC engine room fire stationsD all of the above
单选题Which statement regarding the site-survey process is correct？（）A In a multifloor building， the access point layout from the survey of one floor can be directly applied to the remaining floorsB Access points can be installed in the same place on every floor， without worrying about co-channelinterferenceC You can survey with a Cisco AIR-ANT5959 in a plenum environmentD Identify all hazardous and restricted areas that might require extra or special survey and installationwork
单选题In order to start a large, low-speed, main propulsion diesel engine on high viscosity fuel after an extended shutdown, the （）A fuel must be preheatedB intake air should be preheatedC lube oil outlet temperature should be increased 20℃ above normalD none of the above
单选题With one or more cylinders out of operation, the engine speed must be reduced because（）A in such cases, the air supply is no longer optimal, the thermal load will be higherB governor hunting will occurC torsional vibrations as other mechanical vibrations may occurD all of the above are correct
