Gas masks ______.A.should be worn while fighting a fireB.can be used in atmospheres deficient in oxygenC.filter contaminants from air that is to be breathedD.may be substituted for a self-contained breathing apparatus
Gas masks ______.
A.should be worn while fighting a fire
B.can be used in atmospheres deficient in oxygen
C.filter contaminants from air that is to be breathed
D.may be substituted for a self-contained breathing apparatus
相关考题：
The expansion valve used in a refrigeration system regulates theA.superheat of the gas leaving the compressorB.back pressure in the evaporatorC.temperature in the refrigerated spaceD.degree of superheat of the gas leaving the evaporator
An inert gas system on a tanker should be used to ______.A.prevent the generation of flammable or combustible gas in tanksB.blow out cargo lines to prevent the build up of gas concentrationsC.dilute tank atmospheres to keep gas concentrations below the lower explosive limitD.prevent fires in the pumproom by continually displacing flammable vapors
Which method is used to supply inert gas from a flue gas system to the cargo tanks?A.Exhaust gas pressure from the stackB.High capacity fanC.Inert gas compressorD.Natural aspiration
The fresh air intake of the inert gas system ______，A.Prevents the flue gas from falling below 3% content of oxygenB.Allows the inert gas piping to be used for gas freeing the tanksC.Opens when there is excessive vacuum on the deck water sealD.Enables outside air to mix with and cool hot flue gasses
What is NOT a requirement for the safe and effective use of a crude oil washing system ________．A.Strip all tanks and remove the bottom residueB.Use an inert gas system while washing tanksC.Use portable washing machines to reach areas obscured by structural members in the tanksD.Debottom the tank used as the source for the tank cleaning machines
Which statement about inert gas pressures in a cargo tank is TRUE ________．A.The pressures of the inert gas in the tank may create excessive pressure at the pump while dischargingB.Gas pressures should be maintained at the highest permissible level throughout the discharging processC.High gas pressures may cause pyrophoric oxidation in the tankD.High gas pressures may cause loss of suction when stripping
Which statement is TRUE concerning buoyant work vests aboard tankers ________．A.They may be worn while working on deck but not while working over the sideB.They must be used only under supervision of a designated ship's officerC.They will be accepted for up to 10% of the required life preserversD.They may be worn during drills
Each ship having an inert gas system must have a portable instruments to measure concentrations of hydrocarbon vapor in inert atmospheres and also to measure ______.A.nitrogenB.oxygenC.carbon dioxideD.water vapor
Mail carriers are encouraged to ___comfortable shoes while on duty.A. wore B. wearing C. worn D. wear
What kind of （）can be used for gas and chemical fires?A、equipmentB、apparatusC、extinguishersD、machines
For the IP address 192.168.2.1 which of the following subnet masks would be MOST likely used?（）A、255.255.0.0B、255.255.248.0C、255.255.255.0D、255.255.255.255
单选题Gas masks（）.Ashould be worn while fighting a fireBcan be used in atmosphere deficient in oxygenCfilter contaminants from air that is to be breathedDmay be substituted for a self-contained breathing apparatus
单选题The fresh air intake of the inert gas system（）.Aprevents the flue gas from falling below 3% content of oxygenBallows the inert gas piping to be used for gas freeing the tanksCopens when there is excessive vacuum on the deck water sealDenables outside air to mix with and cool hot flue gasses
单选题For the IP address 192.168.2.1 which of the following subnet masks would be MOST likely used?（）A255.255.0.0B255.255.248.0C255.255.255.0D255.255.255.255
单选题Gas masks（）.Ashould be worn while fighting a fireBcan be used in atmospheres deficient in oxygenCfilter contaminants from air that is to be breathedDmay be substituted for a self-contained breathing apparatus
单选题On all vessels equipped with refrigeration units of over 20 cubic foot capacity, （）.Aa gas mask suitable for protection against each refrigerant used, or a self contained breathing apparatus must be providedBit is the sole responsibility of the chief engineer to ascertain that all members of the engineering department are familiar with the use of gas masks or breathing apparatusCspare charges shall be carried for at least 50% of each size and variety of gas masks and/or self contained breathing apparatusDall of the above
单选题Hot gas bypass is one of the methods used to （）Arelieve excessive compressor head pressureBproduce flash gas at the expansion valveCreduce flooding of the receiver at low loadDdefrost the evaporator coils
单选题The Romans used to sell _____ by auction.Aspoilt goodsBold-worn weaponsCproperty taken from the enemyDspears
单选题Which method is used to supply inert gas from a flue gas system to the cargo tanks?（）AExhaust gas pressure from the stackBHigh capacity fanCInert gas compressorDNatural aspiration
单选题Gas turbines differ from steam turbines in that （）.Asteam rather than gas is used to turn a shaftBvapor rather than gas is used to turn a shaftCthe former uses gas to turn a shaftDthe latter uses gas to turn a shaft
单选题Each ship having an inert gas system must have a portable instruments to measure concentrations of hydrocarbon vapor in inert atmospheres and also to measure（）.AnitrogenBoxygenCcarbon dioxideDwater vapor
单选题An inert gas system on a tanker should be used to（）.Aprevent the generation of flammable or combustible gas in tanksBblow out cargo lines to prevent the build up of gas concentrationsCdilute tank atmospheres to keep gas concentrations below the lower explosive limitDprevent fires in the pumproom by continually displacing flammable vapors
单选题The component in an inert gas system used for cleaning the gas of solid and sulphur combustion products，while simultaneously cooling the inert gas，is called the（）.AfilterBcoolerCscrubberDpurifier
单选题An inert gas system on a tanker should be used to（）.Aprevent the generation of flammable or combustible gas in tanksBblow out cargo lines to prevent gas concentrationsCdilute tank atmospheres to keep gas concentrations below the lower explosive limitDprevent fires in the pumproom by continually displacing flammable vapors
单选题The preferred agent used in fighting a helicopter crash fire is（）.ACO2Bdry chemicalCwaterDfoam