According to ASHRAE standards according to their toxicity and flammability, Class A refrigerant has no toxicity identified even at a low concentration of _______ by volume:

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Related questions
Which of the following diagram is also known as Mollier diagram:
A vent material listed and labeled for use with wall furnaces is type _____ vent.
10oF rise in air temperature can decrease relative humidity ______ :
Pressure drop in the refrigeration system is expressed in terms of:
Shell and tube condenser is similar in construction to the flooded chiller:
A low pressure switch is provided to stop the compressor when the compressor _______ pressure falls below the safety limits:
The ______ connects the compressor to the condenser
Most of the refrigeration gases are heavier than air
Where a liquid line riser becomes necessary to connect to an evaporator located at higher level than the condenser, the pressure drop due to liquid lift will be high causing heavy flash in the liquid line:
The condensing temperature will be higher in air cooled condenser compared to water cooled condenser:
The volumetric efficiency of the compressor reduces as the evaporating temperature ______
As per ASHRAE which of the following refrigerant class has high flammability:
As the condensing temperature increases, centrifugal compressor capacity _______ :
Refrigerants operating in refrigerating systems shall have _______ pressure:
Which of the following refrigerants have greater stability in lower parts of the atmosphere:
The solubility of the water in the commonly used refrigerants is low
The capacity of the refrigeration system is expressed in which of the following units: (Multiple Answer Question)
As the Suction pressure comes down, the compressor capacity will ______:
The pressure drop caused in the suction filter will be ____:
In which of the following pipes the higher-velocity refrigerant is closer to the inner walls of the pipe:
At the right end of the dew point lines, the vertical scale is the Dry bulb temperature:
R-410a is the best replacement for R-22 refrigerant
When the liquid level is below the sensing bulb, the vapor surrounding the bulb carries away the heat from the electric heater at relatively ____ rate:
Freezing point of the refrigerant should be well above the expected evaporator temperature
In which of the following compressor, the piston moves alternatively downwards and upwards in a cylinder:
A mechanical draft venting system shall terminate at least ____ feet above any forced air inlet located within 10 feet.
High molecular weight of the Freon compounds contributes to ____ specific heat values
Vertical lines in Psychromteric charts indicate constant ______ in °C or °F:
The high molecular weight of the Freon compounds contributes to low latent heats of vaporization
Smoke detectors shall be installed in return air systems with a design capacity greater than ________ cfm.
A minimum openable area to the outdoors shall be  ______ percent of the floor area being naturally ventilated.
Vapor can be present in the liquid line, if there is _______ pressure drop in the liquid line:
The CFC and HCFC refrigerants were:
Oil used in refrigeration system is used for which of the following:
Which of the following refrigerant has least density:
The hydrolysis rate for the Freon compounds as a group is _____ compared with other halogenated compounds.
After ______ the servicing of R-22-based systems will rely on recycled refrigerants
The _______ of an oil is the temperature at which wax in the oil begins to precipitate from a mixture of 90% refrigerant and 10% oil by volume:
The solubility of the water in the commonly used refrigerants is high