AND ANSWERS GUARANTEE A+
✔✔In a refrigerant system, the device that changes a low pressure vapor to a high
pressure vapor is the: - compressor. - ✔✔
✔✔Data shows that chlorine in the stratosphere comes mainly from CFCs rather than
from natural sources such as volcanoes because: - The rise in the amount of chlorine in
the stratosphere matches the rise in the amount of fluorine, which has different natural
sources than chlorine; The rise in the amount of chlorine in the stratosphere matches
the rise in CFC emissions; Air samples taken from the stratosphere over erupting
volcanoes show that volcanoes contribute a small quantity of chlorine to the
stratosphere when compared to CFCs; - ✔✔
✔✔Which atom of the CFC molecule causes ozone depletion? - chlorine - ✔✔
✔✔The ozone layer protects the earth from: - ultraviolet radiation from the sun. - ✔✔
✔✔When using with any solvent, cleaner, chemical or refrigerant, you should review: -
material safety data sheets. - ✔✔
✔✔An award of up to what amount may be paid to a person supplying information that
leads to a penalty against a technician who is intentionally venting? - 10,000 - ✔✔
✔✔The Montreal Protocol is: - a treaty among nations that controls production of CFCs
and HCFCs. - ✔✔
✔✔Which refrigerant is an HCFC? - R-123, R-22, R-124 - ✔✔
✔✔What is one of the most serious results of damage to the ozone layer? - increases in
human skin cancer - ✔✔
✔✔Of the refrigerants listed below, which has the lowest ozone depletion potential
(ODP)? - R-22 - ✔✔
✔✔To determine the maximum allowable pressure to use when checking a system,
check: - the design pressure on the equipment nameplate - ✔✔
✔✔Ozone depletion potential, or "ODP," is: - A measure of the ability of CFCs and
HCFCs to destroy ozone. - ✔✔
✔✔An example of an HFC refrigerant is: - R-134a - ✔✔
, ✔✔Whenever dry nitrogen from a portable cylinder is connected to a system, what item
is of most importance in consideration of safety? - There is relief in the downstream line
from the pressure regulator. - ✔✔
✔✔During servicing of a refrigeration system containing R-12, the refrigerant must be: -
recovered. - ✔✔
✔✔Which safety precaution(s) should always be followed: - Never apply an open flame
to a refrigerant cylinder; never cut or weld any refrigerant line when refrigerant is in the
line; never use oxygen to purge lines or to pressurize a system. - ✔✔
✔✔In a vapor compression refrigeration system, cooling occurs when: - refrigerant
liquid turns to a vapor. - ✔✔
✔✔The evacuation of a system is a method of: - dehydration. - ✔✔
✔✔Each chlorine atom in the stratosphere can destroy____ozone molecules. - 100,000
- ✔✔
✔✔An example of a HFC refrigerant is: - R-410A - ✔✔
✔✔Which gas(es) would cause the LEAST damage to the environment during a leak
check? - dry nitrogen - ✔✔
✔✔Refrigerant migrates to the compressor crankcase because of a difference
in______between the refrigerant and the oil. - vapor pressure. - ✔✔
✔✔Which refrigerant is an HCFC? - R-22, R-123, R-124 - ✔✔
✔✔It is important not to mix R-22 and R-410A refrigerants in the same container
because: - the mixture may be impossible to reclaim. - ✔✔
✔✔When using recover unit, the fill level of the recovery tank can be controlled by: - a
mechanical switch; an electronic shut-off device; weight - ✔✔
✔✔Which of the following refrigerant releases is a violation of the EPA prohibition on
venting? - release of mixtures of nitrogen and refrigerant that result from adding
nitrogen to a fully charged appliance to "leak-check" the appliance. - ✔✔
✔✔Which of the following human health effects could result from an increase in
ultraviolet radiation? - an increase in cataracts cases - ✔✔