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EPA 608 study materials
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EPA 608 practice questions

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Question 1Type I - Small Appliances

Technicians who service small appliances must hold which EPA Section 608 certification?

  1. Type II
  2. Universal
  3. Type I Correct answer.
  4. Type III

Explanation

Type I certification covers the service, maintenance, and disposal of small appliances, which are factory-charged, hermetically sealed units containing 5 pounds or less of refrigerant. The other certifications apply to different equipment categories.

Question 2Type I - Small Appliances

When recovering refrigerant from a small appliance, the recovery equipment must remove at least what portion of the charge?

  1. 90 percent of the total charge
  2. 85 percent of the total charge
  3. 95 percent of the total charge
  4. 80 percent of the total charge Correct answer.

Explanation

EPA rules require that recovery equipment used on small appliances recover at least 80 percent of the refrigerant charge, regardless of when the equipment was manufactured. Higher recovery percentages apply to certain other appliance categories.

Question 3Type I - Small Appliances

An appliance qualifies as a small appliance under Section 608 when it contains 5 pounds or less of refrigerant and is

  1. equipped with a liquid receiver
  2. installed inside a residence
  3. field-assembled on site with service valves
  4. hermetically sealed and factory-charged Correct answer.

Explanation

The regulatory definition requires the unit to be fully manufactured, charged, and hermetically sealed in a factory with 5 pounds or less of refrigerant. How or where the unit is installed does not determine the category.

Question 4Type I - Small Appliances

Which action is prohibited when servicing a small appliance?

  1. Venting refrigerant vapor to the atmosphere Correct answer.
  2. Recovering refrigerant into a DOT-approved recovery cylinder
  3. Charging recovered refrigerant back into the same appliance
  4. Recycling refrigerant through filter-driers before reuse

Explanation

Section 608 prohibits knowingly venting ozone-depleting refrigerants and their substitutes to the atmosphere during service, maintenance, or disposal. Recovered refrigerant must be recovered, recycled, or reclaimed instead.

Question 5Type I - Small Appliances

A recovery cylinder should be filled with liquid refrigerant to no more than what level?

  1. 100 percent of its weight capacity
  2. 95 percent of its volume capacity
  3. 90 percent of its weight capacity
  4. 80 percent of its weight capacity Correct answer.

Explanation

Cylinders must be filled by weight and never exceed 80 percent of capacity so that a vapor space remains for liquid expansion. Overfilling can cause hydrostatic pressure to rupture the cylinder.

Question 6Type I - Small Appliances

Under EPA regulations, who may purchase refrigerant?

  1. Any appliance owner
  2. Only licensed contractors
  3. Any member of the public
  4. Only certified technicians Correct answer.

Explanation

Refrigerant may be sold only to technicians certified under Section 608. Possession of a business license or ownership of an appliance does not authorize purchase.

Question 7Type I - Small Appliances

Which of the following is classified as a small appliance under Section 608?

  1. A rooftop unit with a 15-pound charge
  2. A centrifugal chiller
  3. A window air conditioner Correct answer.
  4. A supermarket refrigeration rack

Explanation

Window air conditioners are factory-charged, hermetically sealed units with 5 pounds or less of refrigerant, so they are small appliances. Racks, rooftop units with larger charges, and chillers fall under other certifications.

Question 8Type I - Small Appliances

Which personal protective equipment is most important when handling liquid refrigerant?

  1. A dust mask and cotton work gloves
  2. Safety glasses and insulated work gloves
  3. A respirator and hearing protection
  4. Safety glasses and impervious gloves Correct answer.

Explanation

Liquid refrigerant boils at extremely low temperature and can cause frostbite and permanent eye damage on contact. Impervious gloves and eye protection are the essential protection; ordinary cloth or insulated gloves absorb liquid and make injury worse.

Question 9Type I - Small Appliances

A technician is asked to repair a packaged unit that contains 12 pounds of R-410A. Which certification does this work require?

  1. Type III
  2. Type I
  3. No certification is required
  4. Type II Correct answer.

Explanation

Appliances containing more than 5 pounds of a high-pressure refrigerant fall outside the small appliance category and require Type II certification. Type I is limited to appliances with 5 pounds or less.

Question 10Type I - Small Appliances

What is the difference between recycling and reclaiming refrigerant?

  1. Recycling applies only to HFCs; reclaiming applies only to CFCs
  2. Recycling cleans refrigerant on site; reclaiming restores ARI 700 purity Correct answer.
  3. Recycling is performed only by manufacturers; reclaiming is performed by technicians
  4. Recycling restores refrigerant to ARI 700 purity, while reclaiming only removes oil and moisture

Explanation

Recycling reduces contaminants such as oil, moisture, and acid, usually on site with filter-driers, and the result may not meet ARI 700. Reclaiming is reprocessing at a certified facility to meet ARI 700 purity specifications.

Question 11Type I - Small Appliances

A technician recovers R-134a from a customer's refrigerator. Which use of that refrigerant is allowed without sending it to a reclaimer?

  1. Charging it into a different customer's refrigerator
  2. Storing it long-term in a disposable cylinder
  3. Returning it to the same refrigerator Correct answer.
  4. Selling it to another certified technician

Explanation

Recovered refrigerant may be reused without reclamation only in the appliance it came from or in another appliance owned by the same person. Any other use requires reclaiming to ARI 700 purity.

Question 12Type I - Small Appliances

How should a blended refrigerant such as R-410A be charged into a small appliance?

  1. As a vapor to prevent compressor slugging
  2. As a vapor through the suction service port
  3. As a liquid to prevent fractionation Correct answer.
  4. As a gas after warming the cylinder

Explanation

Blends are mixtures whose components have different boiling points, so vapor charging draws off the components unevenly and changes the mixture. They must be removed from the cylinder as a liquid so the original composition is maintained.

Question 13Type I - Small Appliances

Which instrument confirms that a system has been evacuated to the required level?

  1. A water manometer
  2. A micron gauge Correct answer.
  3. A psychrometer
  4. A compound gauge

Explanation

A micron gauge measures deep vacuum in microns, which is far below the resolution of ordinary pressure gauges. Manifold gauges cannot indicate whether the required vacuum level has actually been reached.

Question 14Type I - Small Appliances

Which gas should be used to pressure-test a small appliance after a repair?

  1. Acetylene
  2. Oxygen
  3. Dry nitrogen Correct answer.
  4. Compressed air

Explanation

Dry nitrogen is inert and is applied through a pressure regulator for leak-checking and pressure testing. Oxygen, air, and fuel gases can explode or burn when combined with refrigerant oil and heat.

Question 15Type I - Small Appliances

Which method is appropriate for locating a small refrigerant leak on an HFC-134a appliance?

  1. A water-filled U-tube manometer
  2. A halide torch flame test
  3. A sling psychrometer reading
  4. An electronic leak detector Correct answer.

Explanation

Electronic leak detectors are designed to sense HFC refrigerants at low concentrations. Halide torches are intended for CFC and HCFC refrigerants and are not suitable for HFCs.

Question 16Type I - Small Appliances

Recovery equipment intended for use on small appliances must be certified by

  1. the refrigerant supplier
  2. an EPA-approved testing organization Correct answer.
  3. the local municipal building department
  4. the appliance manufacturer

Explanation

Recovery and recycling equipment must be tested and certified by an organization approved by EPA to verify that it meets the required recovery efficiency. Manufacturer, municipal, or supplier approval does not satisfy this requirement.

Question 17Type I - Small Appliances

Why should the appliance's own compressor never be used as a vacuum pump?

  1. It adds too much oil to the system
  2. It removes the refrigerant too quickly
  3. It voids the appliance warranty
  4. It cannot pull a deep vacuum and may overheat Correct answer.

Explanation

A refrigeration compressor is designed to pump vapor against high discharge pressure, not to evacuate a system to a deep vacuum. Running it for evacuation can overheat or damage it and will not reach the required vacuum level.

Question 18Type I - Small Appliances

A small appliance's compressor will not run, and the refrigerant must still be removed. Which statement is correct?

  1. Recovery is still required and may take longer Correct answer.
  2. The charge may be vented because the compressor is dead
  3. The refrigerant must be burned off on site
  4. Recovery is unnecessary because the charge is trapped in the condenser

Explanation

The recovery requirement applies whether or not the compressor operates. A non-running compressor means the system cannot help move refrigerant, so recovery with the recovery machine may take more time and care.

Question 19Type I - Small Appliances

A recovery cylinder contains refrigerant that may be a mixture of two different refrigerants. What should be done with it?

  1. Ship it to an EPA-certified refrigerant reclaimer Correct answer.
  2. Charge it into any appliance that uses one of the refrigerants
  3. Blend it with virgin refrigerant to restore purity
  4. Vent it to the atmosphere since it cannot be reclaimed

Explanation

Mixed refrigerants cannot be separated in the field, so the cylinder must be sent to an EPA-certified reclaimer. Mixing also makes the entire batch unreclaimable, so different refrigerants must always be kept in separate cylinders.

Question 20Type I - Small Appliances

How often must a DOT recovery cylinder be hydrostatically tested?

  1. Every year
  2. Every 10 years
  3. Every 5 years Correct answer.
  4. Only when it is damaged

Explanation

Refrigerant cylinders are DOT-specified pressure vessels that must be requalified by hydrostatic test every 5 years. A cylinder past its test date may not be filled.

Question 21Type I - Small Appliances

When a CFC refrigerant contacts an open flame, which toxic gas can be formed?

  1. Sulfur dioxide
  2. Hydrogen sulfide
  3. Carbon monoxide
  4. Phosgene Correct answer.

Explanation

Heating CFC refrigerants with a torch decomposes them into phosgene, a highly toxic gas; HFCs break down into hydrogen fluoride. Lines should be evacuated and purged before any brazing.

Question 22Type I - Small Appliances

Why is a refrigerant leak in a basement mechanical room a serious hazard?

  1. It reacts with concrete to form corrosive acid
  2. It raises the room pressure to a dangerous level
  3. It is heavier than air and can displace oxygen Correct answer.
  4. It ignites easily at low concentrations

Explanation

Refrigerant vapor is denser than air and settles in low areas such as basements and pits, displacing the oxygen supply. Ventilation and monitoring are needed before entering such spaces.

Question 23Type I - Small Appliances

A frost-free refrigerator has a leaking evaporator that cannot be repaired. What is the correct action?

  1. Recover the charge, then scrap the appliance Correct answer.
  2. Drain the oil and scrap it without recovering
  3. Seal the leak with epoxy and resell the unit
  4. Vent the remaining charge, then scrap the unit

Explanation

Refrigerant must be recovered before an appliance is opened, dismantled, or discarded, even when the unit is being destroyed. Venting during disposal is prohibited.

Question 24Type I - Small Appliances

Why must a recovery cylinder never be filled completely with liquid refrigerant?

  1. The cylinder gauge will read inaccurately
  2. Liquid refrigerant will not flow out of the valve
  3. Liquid expansion can rupture the cylinder Correct answer.
  4. The refrigerant will decompose under pressure

Explanation

Liquid refrigerant expands significantly as it warms, and with no vapor space the pressure can rise until the cylinder fails. Filling by weight to no more than 80 percent keeps a vapor space for expansion.

Question 25Type I - Small Appliances

How must polyolester (POE) oil used with HFC refrigerants be handled?

  1. Stored in open containers so acids can escape
  2. Mixed with mineral oil before use
  3. Replaced after every service call
  4. Kept sealed because it absorbs moisture quickly Correct answer.

Explanation

POE oil is hygroscopic and takes on moisture from the air rapidly, which can lead to acid formation and system damage. Containers should be kept closed and opened only briefly during use.

Question 26Type I - Small Appliances

Under Section 608, what is the maximum refrigerant charge, in pounds, that defines a small appliance?

  1. 10 pounds
  2. 15 pounds
  3. 25 pounds
  4. 5 pounds Correct answer.

Explanation

A small appliance is defined as an appliance containing 5 pounds or less of refrigerant, excluding motor vehicle air conditioners. Any charge above that threshold falls under a different servicing category.

Question 27Type I - Small Appliances

Which certification category must a technician hold to service a small appliance containing 5 pounds or less of refrigerant?

  1. Type II
  2. Type III
  3. Type I Correct answer.
  4. Universal

Explanation

Type I certification covers the servicing of small appliances. Type II covers high-pressure appliances, Type III covers low-pressure appliances, and Universal covers all categories.

Question 28Type I - Small Appliances

Which refrigerant is classified as a chlorofluorocarbon (CFC)?

  1. R-410A
  2. R-134a
  3. R-22
  4. R-12 Correct answer.

Explanation

R-12 contains chlorine and fluorine and is classified as a CFC. R-22 is an HCFC, while R-134a and R-410A are HFCs.

Question 29Type I - Small Appliances

What color identifies the top of a recovery cylinder used for recovered refrigerant?

  1. Green
  2. Red
  3. Gray
  4. Yellow Correct answer.

Explanation

Recovery cylinders generally have a gray body and a yellow top. The yellow top signals that the cylinder is intended for recovered refrigerant.

Question 30Type I - Small Appliances

Before a household refrigerator is scrapped, what must be done with the refrigerant?

  1. Burn it
  2. Vent it
  3. Dilute it with water
  4. Recover it Correct answer.

Explanation

Refrigerant must be recovered before an appliance is dismantled or discarded. Knowingly venting refrigerant to the atmosphere is prohibited under Section 608.

Question 31Type I - Small Appliances

Which lubricant is commonly used with HFC-134a in small appliances?

  1. Silicone oil
  2. Polyolester oil Correct answer.
  3. Castor oil
  4. Mineral oil

Explanation

HFC refrigerants such as R-134a generally require polyolester (POE) lubricant. Mineral oil is typically used with CFC and HCFC refrigerants.

Question 32Type I - Small Appliances

What does Section 608 prohibit when servicing a small appliance?

  1. Using a gauge manifold
  2. Knowingly venting refrigerant Correct answer.
  3. Using a vacuum pump
  4. Using a recovery cylinder

Explanation

Section 608 prohibits knowingly venting ozone-depleting refrigerants and their substitutes during service, maintenance, repair, or disposal. Recovery equipment must be used instead.

Question 33Type I - Small Appliances

What is the maximum percentage of a recovery cylinder that may be filled with liquid refrigerant?

  1. 80 percent Correct answer.
  2. 90 percent
  3. 95 percent
  4. 100 percent

Explanation

A recovery cylinder must never be filled beyond 80 percent of its capacity by weight. Leaving vapor space allows for liquid expansion as the cylinder warms.

Question 34Type I - Small Appliances

A technician recovers refrigerant from a small appliance manufactured before November 15, 1993, without evacuating to 4 inches Hg. What minimum percentage of the charge must be recovered?

  1. 80 percent Correct answer.
  2. 70 percent
  3. 50 percent
  4. 90 percent

Explanation

For pre-1993 small appliances, the technician must recover at least 80 percent of the refrigerant charge or evacuate the system to 4 inches Hg vacuum. Recovery to a lower percentage does not meet the requirement.

Question 35Type I - Small Appliances

For a small appliance manufactured after November 15, 1993, what minimum percentage of refrigerant must be recovered if the system is not evacuated to 4 inches Hg?

  1. 90 percent Correct answer.
  2. 70 percent
  3. 100 percent
  4. 80 percent

Explanation

Post-1993 small appliances require recovery of at least 90 percent of the charge unless the system is evacuated to 4 inches Hg. The higher percentage reflects the newer equipment standard.

Question 36Type I - Small Appliances

When system-dependent recovery equipment is used on a small appliance manufactured after November 15, 1993, to what vacuum must the system be evacuated?

  1. 20 inches Hg
  2. 10 inches Hg Correct answer.
  3. 4 inches Hg
  4. 0 inches Hg

Explanation

System-dependent recovery equipment on post-1993 small appliances must evacuate the system to 10 inches Hg vacuum. This is a lower vacuum than the 4 inches Hg requirement for pre-1993 appliances.

Question 37Type I - Small Appliances

When system-dependent recovery equipment is used on a pre-1993 small appliance, what is the required evacuation level?

  1. 4 inches Hg Correct answer.
  2. 10 inches Hg
  3. 20 inches Hg
  4. 0 inches Hg

Explanation

Pre-1993 small appliances using system-dependent recovery equipment must be evacuated to 4 inches Hg vacuum. Post-1993 appliances have a different system-dependent requirement.

Question 38Type I - Small Appliances

A recovery cylinder has reached 80 percent of its capacity by weight. What should the technician do?

  1. Stop recovery and use another cylinder Correct answer.
  2. Cool the cylinder and keep filling
  3. Vent excess refrigerant to make room
  4. Continue until the cylinder is full

Explanation

Recovery must stop at 80 percent capacity by weight so the cylinder has room for liquid expansion. The remaining refrigerant should be directed into another recovery cylinder.

Question 39Type I - Small Appliances

How should a recovery cylinder be transported in a service vehicle?

  1. Lying unsecured in the trunk
  2. On its side in the passenger cab
  3. In the passenger seat with a seatbelt
  4. Secured upright in the cargo area Correct answer.

Explanation

Recovery cylinders should be secured upright in the cargo area so the valve is protected and the cylinder cannot roll. They should not be carried loose or in the passenger compartment.

Question 40Type I - Small Appliances

What is the purpose of a filter-drier installed on a recovery machine?

  1. Increase recovery speed
  2. Remove moisture and acids Correct answer.
  3. Measure vacuum level
  4. Cool the refrigerant

Explanation

A filter-drier removes moisture, acids, and particulate contamination from refrigerant passing through the recovery machine. This helps protect the recovery equipment and the refrigerant quality.

Question 41Type I - Small Appliances

For what situation is a recovery bag designed?

  1. Systems containing more than 15 pounds
  2. Sealed units with a dead compressor Correct answer.
  3. Large commercial chillers and racks
  4. Motor vehicle air-conditioning systems

Explanation

A recovery bag is used on non-pressurized small appliances that have no service ports and an inoperative compressor. It captures refrigerant that cannot be removed with system-dependent equipment.

Question 42Type I - Small Appliances

When adding refrigerant vapor to a small appliance, where should it be introduced?

  1. Into the discharge line before the condenser
  2. Into the compressor oil sump
  3. Into the liquid line while the system is off
  4. Into the suction line while the system runs Correct answer.

Explanation

Vapor refrigerant should be charged into the suction line with the system operating so the compressor does not slug liquid. Liquid charging is handled differently and depends on the refrigerant type.

Question 43Type I - Small Appliances

Before recovering refrigerant from a small appliance of unknown service history, what should the technician do first?

  1. Identify the refrigerant Correct answer.
  2. Evacuate the system
  3. Add nitrogen to the system
  4. Heat the recovery cylinder

Explanation

The refrigerant should be identified before recovery so it is not mixed with a different refrigerant in the recovery cylinder. A refrigerant identifier can determine the type and help detect contamination.

Question 44Type I - Small Appliances

What leak repair requirement does Section 608 impose on small appliances?

  1. No mandatory leak repair Correct answer.
  2. Repair within 7 days
  3. Repair only if charge exceeds 5 pounds
  4. Repair within 30 days

Explanation

The mandatory leak repair requirements apply to appliances containing 50 or more pounds of refrigerant. Small appliances are not subject to those repair deadlines.

Question 45Type I - Small Appliances

What is the maximum temperature to which a recovery cylinder should be heated?

  1. 125 degrees F Correct answer.
  2. 200 degrees F
  3. 175 degrees F
  4. 150 degrees F

Explanation

A recovery cylinder should never be heated above 125 degrees F. Warm water or a gentle heating blanket may be used, but an open flame or excessive heat is unsafe.

Question 46Type I - Small Appliances

A technician allows a small amount of refrigerant to escape while connecting gauges to a small appliance. Which statement best describes the EPA requirement?

  1. Any release is allowed during repair
  2. Release is allowed for R-134a but not for R-12
  3. Release is allowed if it is under 1 pound
  4. Knowing venting is prohibited and connections must minimize release Correct answer.

Explanation

Section 608 prohibits knowingly venting refrigerant, and service practices must minimize releases. Low-loss fittings and proper hose handling reduce the amount released during gauge connections.

Question 47Type I - Small Appliances

Refrigerant recovered from a small appliance with a burned-out compressor should be handled how?

  1. Vented if the quantity is small
  2. Recycled or reclaimed with filtration before reuse Correct answer.
  3. Returned directly to the same appliance
  4. Mixed with other refrigerant in a recovery cylinder

Explanation

A compressor burnout can leave acids and particulate contamination in the refrigerant. The recovered refrigerant should be cleaned through recycling or reclaiming before it is reused.

Question 48Type I - Small Appliances

What distinguishes a DOT recovery cylinder from a disposable refrigerant cylinder?

  1. Disposable cylinders are always yellow
  2. Recovery cylinders can be refilled and require hydrostatic testing Correct answer.
  3. Disposable cylinders can be refilled if labeled
  4. Recovery cylinders are never tested

Explanation

DOT recovery cylinders are designed to be refilled and must be hydrostatically tested on a required schedule. Disposable cylinders are not intended to be refilled.

Question 49Type I - Small Appliances

Why must HFC refrigerants be recovered rather than vented even though they do not deplete stratospheric ozone?

  1. They are flammable
  2. They are toxic to plants
  3. They have high global warming potential Correct answer.
  4. They react with nitrogen in the air

Explanation

HFCs are ozone-friendly compared with CFCs, but they are potent greenhouse gases with high global warming potential. Section 608 therefore prohibits knowingly venting them.

Question 50Type I - Small Appliances

A technician must recover refrigerant from a sealed small appliance that has no service ports. Which approach is appropriate?

  1. Use the appliance compressor as a vacuum pump
  2. Install access fittings or use a recovery bag Correct answer.
  3. Vent the charge to the atmosphere
  4. Fill the system with nitrogen and release the mixture

Explanation

When no service ports exist, the technician must gain access by installing fittings or use equipment designed for sealed systems, such as a recovery bag. The refrigerant must still be captured rather than released.