EPA Core Exam

HCFC refrigerants are;

less harmful to stratospheric ozone than CFCs.

Whenever working with any solvents, chemicals and refrigerants, the technician should review;

material safety data sheets.

All devices used for refrigerant recovery must;

meet EPA standards.

Ozone in the atmosphere above the earth consists of;

molecules containing 3 oxygen atoms.

R-134a refrigerant charged systems should be leak checked with;

pressurized nitrogen.

A refrigerant oil that is hygroscopic;

readily absorbs moisture.

Before you dispose of any appliance containing a CFC or HCFC refrigerant, you must;

recover the refrigerant.

Removing refrigerant in any condition from a system and storing it in an external container without necessarily testing or processing it in any way defines;

recovering.

After 1995, supplies of CFC refrigerant for equipment servicing will come from;

recovery and recycling.

Recovery during low ambient temperatures will;

slow the recovery process.

Refrigerant entering the compressor of a refrigeration system is a;

superheated vapor.

Recovery equipment that relies upon the compressor in the appliance and/or the pressure of the refrigerant in the appliance would be considered;

system-dependent.

The term used to describe the fact that a refrigerant blend has a range of boiling or condensing points at a constant pressure is;

temperature glide.

When recovering refrigerant, it is important not to mix different refrigerants in the same container because;

the mixture may be impossible to reclaim.

If a system will not hold a vacuum after it has been evacuated, then;

the system may be leaking.

A system is said to be dehydrated when;

the vacuum indicator shows you have reached and held the required finished vacuum.

A hermetic compressor must never be operated when;

there is a dehydration vacuum in the system.

Refrigerant vapors or mists in high concentrations should not be inhaled since;

they may cause heart irregularities or unconsciousness.

The ozone layer protects the earth from;

ultraviolet radiation from the sun.

What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine?

CFCs neither dissolve in water nor break down into compounds that dissolve in water, so they do not rain out of the atmosphere.

Which compounds have the highest ozone depletion potential (ODP)?

CFCs.

When pressurizing a refrigeration system with nitrogen what rule should you always follow?

Charge through a pressure regulator.

What chemical found in the upper stratosphere indicates that the ozone layer is being destroyed?

Chlorine monoxide.

Which atom of the CFC molecule causes ozone depletion?

Chlorine.

Factors affecting the speed of evacuation include; A. the size of the equipment being evacuated. B. the ambient temperature. C. the amount of moisture in the system.

D. All of the above.

Service technicians who violate Clean Air Act provisions; A. may be fined. B. may lose certification. C. may be required to appear in Federal court.

D. All of the above.

What effects can ozone depletion have on the environment? A. Reduced crop yields. B. Reduced marine life. C. Increased ground-level ozone.

D. All of the above.

What is being done in the U.S. to stop damage to the stratospheric ozone layer? A. Using natural gas instead of coal to generate electricity. B. Capturing and ultimately eliminating use of chlorofluorocarbons. C. Enforcing strict emission requirements on incinerators.

D. All of the above.

When operating refrigerant recovery or recycling equipment, the following precautions should be followed; A. Wear safety glasses. B. Wear protective gloves. C. Follow all safety precautions for the equipment.

D. All of the above.

Which of the following is/are violation(s) of the Clean Air Act? A. Falsifying or failing to keep required records. B. Failing to reach required evacuation levels before opening or disposing of appliances. C. Knowingly releasing CFC or HCFC refrigerants or their substitutes while repairing appliances.

D. All of the above.

Which refrigerant(s) must be recovered before opening or disposing of appliances? A. R-12. B. R-22. C. R-500.

D. All of the above.

Some state and local governments may establish laws that; A. follow the Clean Air Act/EPA regulations. B. are not as strict as the Clean Air Act/EPA regulations. C. contain stricter regulations than the Clean Air Act/EPA regulations.

D. Both "A" and "C".

Which of the following leak detection methods is considered to be the most effective for locating the general area of a small leak?

Electronic or ultrasonic tester.

Which refrigerant contains a CFC?

R-500

Which process applies to cleaning refrigerant for immediate reuse by oil separation and single or multiple passes through devices, like replaceable core filter-driers, which reduce moisture and acidity?

Recycling.

Which of the following gases help form the earth's protective shield?

Stratospheric Ozone.

When transporting cylinders containing used refrigerant, DOT requires that you;

attach DOT classification tags.

The component of a refrigeration system which changes a high pressure vapor to a high pressure liquid is the;

condenser.

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

Each chlorine atom in the stratosphere can destroy ___________ ozone molecules.

100,000

Ozone depletion in the stratosphere is what type of problem?

Global.

Which refrigerant is a chlorine -free refrigerant?

HFC-134a.

Which of the following refrigerants will NOT damage stratospheric ozone?

HFCs.

Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) have which of the following in common?

They must be recovered before opening or disposing of appliances.

How should refrigerant cylinders be positioned when they are shipped?

Upright.

The synthetic lubricant presently used with ternary blends containing HCFCs is;

alkylbenzene.

For accurate readings during evacuation, the system vacuum gauge should be connected;

as far from the vacuum pump as possible.

Blended refrigerants leak from a system;

at uneven rates due to different vapor pressures.

One instance when personal protective equipment (gloves, safety glasses, safety shoes, etc.) should be worn is when;

handling and filling refrigerant cylinders.

The state of the refrigerant leaving the condenser of a refrigeration system is;

high pressure liquid.

Hydro fluorocarbon (HFC) refrigerants contain;

hydrogen, fluorine & carbon.