EPA 608 CORE – Practice Test 2

Correct answer is D:  All of the above.

Which safety precaution(s) should always be followed?

• Never apply an open flame to a refrigerant cylinder.
• Never cut or weld any refrigerant line while refrigerant is in the line.
• Never use oxygen to purge lines or to pressurize a system.

Correct answer is A:  refrigerant liquid turns to a vapor.

In a vapor compression refrigeration system, cooling occurs when refrigerant liquid turns to a vapor.

Correct answer is C:  dehydration. 

The evacuation of a system is a method of dehydration

.

The correct answer is D:  100,000

Each chlorine atom in the stratosphere can destroy 100,000 ozone molecules.

Correct answer is D:  R-410a

An example of an HFC refrigerant is R-410a.

• R-11 is a CFC
• R-124 is an HCFC
• R-142b is an HCFC

Correct answer is D:  Dry Nitrogen.

Which gas(es) would cause the LEAST damage to the environment during a leak check?  Dry Nitrogen.

Correct answer is A:  vapor pressure

Refrigerant migrates to the compressor crankcase because of a difference in vapor pressure between the refrigerant and the oil.

Correct answer is A: R-22

Which refrigerant is an HCFC?   R-22

• R-22 is a HCFC
• R-134a is a HFC
• R-410a is a HFC
• R-12 is a CFC

Correct answer is A:  the mixture may be impossible to reclaim.

It is important not to mix R-22 and R-410a refrigerants in the same container because the mixture may be impossible to reclaim.

Correct answer is D:  All of the above.

When using a recovery unit, the fill level of the recovery tank can be controlled by any of following:

• a mechanical float switch.
• an electronic shutoff device.
• weight.

<Correct answer is B:  Release of mixtures of nitrogen and refrigerant that result from adding nitrogen to a fully charged appliance while leak-checking that appliance.

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 while leak-checking that appliance.

Correct answer is A:  An increase in eye cateracts cases.

Which of the following human health effects could result from an increase in ultraviolet radiation?  An increase in eye cateracts cases.

Correct answer is D: All of the above.

Never use an open flame to heat a refrigerant tank because of any of the following reasons;

• A.  it can result in venting refrigerant to the atmosphere.
• B.  the tank may explode causing serious injury to people nearby.
• C.  refrigerant in the tank may decompose, forming a toxic material.

Correct answer is B:  attach DOT classification tags.

When transporting cylinders containing used refrigerant, the DOT requires that you attach DOT classification tags.

Correct answer is A:  A-1

According to ASHRAE’s 1992 refrigerant safety classification, which of the following designations would be the most safe?   A-1

NT Note:

Each ASHRAE safety classification contains two parts: The letter designation (A or B) indicates toxicity, and the number designation (1 thru 3) indicates flammability. So an A-1 classification indicates the lowest toxicity and no flame propagation.

• A-1 = Lower toxicity / No flame propagation
• A-2 = Lower toxicity /  Lower flammability
• A-3 = Lower toxicity /  Higher flammability
• B-1 = Higher toxicity /  No flame propagation
• B-2 = Higher toxicity /  Lower flammability
• B-3 = Higher toxicity /  Higher flammability

Correct answer is D:  does not occur.

The over-evacuation of a system does not occur.

Correct answer is C:  all air-conditioning and refrigeration equipment using CFC, HCFC, or HFC refrigerants.

Equipment covered by EPA regulations include all air-conditioning and refrigeration equipment using CFC, HCFC, or HFC refrigerants.

Correct answer is B:  the internal pressure of the cylinders may rise in heated areas and cause an explosion.

Never overfill refrigerant storage cylinders because the internal pressure of the cylinders may rise in heated areas and cause an explosion.

Correct answer is A:  the mixture may be impossible to reclaim.

It is important not to mix different refrigerants in the same container because the mixture may be impossible to reclaim.

The correct answer is C:  blue.

Manifold gauge sets are often color coded. When they are, the low pressure gauge is colored blue.

Correct answer is D:   meet EPA standards.

All devices used for refrigerant recovery must meet EPA standards.

Correct answer is D:  5 years.

Reusable refrigerant containers that are normally under any pressure above 15 psig, must be hydrostatically tested and date stamped every 5 years.

Correct answer is D:  All refrigerants must be recovered.

Which refrigerant(s) must be recovered before opening a system or disposing of a system?   All refrigerants must be recovered.

Correct answer is B:  as far from the vacuum pump as possible.

To obtain an accurate vacuum reading during system evacuation, the system vacuum gauge should be located as far from the vacuum pump as possible.

Correct answer is C:  The measurement of CFCs in air samples from the stratosphere.

What is the best proof of CFCs in the stratosphere?  The measurement of CFCs in air samples from the stratosphere.