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EPA 608 Universal Exam | 100% Correct
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Refrigeration technicians who violate the Clean Air Act can: - - โโLose their EPA certification, be fined, be required to appear in Federal court. After 1995, any supplies of CFC refrigerants to service existing units in the USA can only come from: - - โโrecovery and recycling. Refrigerant that is recovered can be returned to: - - โโthe same system or other systems owned by the same person without restriction. Refrigerant can not be called "reclaimed" unless it: -. - โโhas been chemically analyzed and the refrigerant meets the ARI-700 standard. The EPA can require a technician to demonstrate their ability to perform proper procedures for recovering and/or recycling refrigerant. Failure to demonstrate competency can result in: - - โโrevocation of the technicians certification. What characteristic(s) of CFCs make them more likely to reach the stratosphere than most other compounds containing chlorine? - - โโRefrigerants that contain chlorine but not hydrogen are so stable that they do not break down in the lower atmosphere after being released. The chlorine or bromine reacts with the ozone, causing it to change back to oxygen, thus destroying the ozone layer. A system is considered dehydrated when: - - โโthe vacuum indicator shows you have reached and held the required finished vacuum. Disposable refrigerant containers are used for ______ - โโvirgin refrigerant Which refrigerant is an HCFC? - - โโR-123, R-124, R- 22
What statement is true about an azeotropic refrigerant mixture? - - โโIt is a mixture that acts like a single-component refrigerant over its entire range. Chlorofluorocarbos (CFCs) and hydrochlorofluorocarbons (HCFCs) have which of the following in common? - - โโIt is a mixture that acts like a single-component refrigerant over its entire range. To scrap a disposable cylinder, the internal cylinder pressure should be reduced to at least: - - โโ0 psig. Manifold gauge sets are often color coded, when this is done, the high pressure gauge is color coded: - Red. - โโ In general, blended refrigerants should be charged: - - โโas a liquid. Blended refrigerants leak from a system: - - โโin uneven amounts due to different vapor pressures. Which of the following gases help form the earth's protective shield? - Stratospheric Ozone - โโ In a refrigerant system, the device that changes a low pressure vapor to a high pressure vapor is the: - compressor. - โโ 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; - โโ Which atom of the CFC molecule causes ozone depletion? - chlorine - โโ The ozone layer protects the earth from: - ultraviolet radiation from the sun. - โโ
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. - โโ In a vapor compression refrigeration system, cooling occurs when: - refrigerant liquid turns to a vapor. - โโ The evacuation of a system is a method of: - dehydration. - โโ Each chlorine atom in the stratosphere can destroy____ozone molecules. - 100,000 - โโ An example of a HFC refrigerant is: - R-410A - โโ Which gas(es) would cause the LEAST damage to the environment during a leak check? - dry nitrogen - โโ Refrigerant migrates to the compressor crankcase because of a difference in______between the refrigerant and the oil. - vapor pressure. - โโ Which refrigerant is an HCFC? - R-22, R-123, R- 124 - โโ It is important not to mix R-22 and R-410A refrigerants in the same container because: - the mixture may be impossible to reclaim. - โโ When using recover unit, the fill level of the recovery tank can be controlled by: - a mechanical switch; an electronic shut-off device; weight - โโ 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. - โโ
Which of the following human health effects could result from an increase in ultraviolet radiation? - an increase in cataracts cases - โโ Never use an open flame to heat a refrigerant tank because: - it can result in venting refrigerant to the atmosphere; the tank may explode, causing serious injury to people nearby; refrigerant in the tank may decompose, forming a toxic material. - โโ When transporting cylinders containing used refrigerant, the DOT requires that you: - attach DOT classification tags - โโ According to ASHRAE's 1992 refrigerant safety classification which of the following designations would be the most safe? - A- 1 - โโ The over-evacuation of a system: - does not occur. - โโ Equipment covered by EPA regulations include: - all air-conditioning and refrigeration equipment using CFC, HCFC or HFC refrigerants. - โโ Never overfill refrigerant storage cylinders because: - the internal pressure of the cylinders may rise in heated areas and cause an explosion. - โโ It is important not to mix different refrigerants in the same container because: - the mixture may be impossible to reclaim. - โโ Manifold gauge sets are often color coded, when this is done, the low pressure gauge is color coded: - blue. - โโ All devices used for a refrigerant recovery must: - Meet EPA standards - โโ Reusable refrigerant containers that are normally under any pressure above 15 pig must be hydrostatically tested and date stamped every: - 5 Years - โโ
Which type of refrigerant is the most harmful to stratospheric ozone? - Refrigerants containing Bromine - โโ According to the EPA, a_______ leak detection method is considered to be the most effective for locating the general area of a small leak. - electronic or ultrasonic tester - โโ Long hoses between the unit and the recovery machine should not be used because they cause: - excessive pressure drop; increased recovery time; increased emissions - โโ Recovery equipment that relies upon the compressor in the system would be considered: - system- dependent. - โโ A hermetic compressor must never be operated when: - there is a dehydration vacuum in the system. - โโ "Self-contained" recovery devices: - can capture liquid and/or vapor refrigerant without the assistance of components in the air-conditioning or refrigeration equipment. - โโ Systems charged with R-410A should be leak checked with: - pressurized nitrogen. - โโ R-410A is not a typical blended refrigerant because: - It is near azeotropic refrigerant; it can be charged as either a liquid or vapor; while it has a 400 series refrigerant number it behaves like a 500 series refrigerant - โโ A ternary refrigerant blend is a _______ part mixture. - three-part - โโ In a refrigeration system, high pressure vapor is converted to high pressure liquid in the: - condenser. - โโ Which of the following is an approved "drop-in" service replacement for r-12? - According to the EPA there are no "drop-in" replacements - โโ
The proper method of discarding a disposable refrigerant cylinder is to: - assure that all refrigerant is recovered and that the cylinder is rendered useless, then recycle the metal. - โโ CFC refrigerants are so named because they contain the elements: - Chlorine, fluorine, carbon - โโ Before you dispose of any system containing a refrigerant, you must: - recover the refrigerant. - โโ According to EPA regulations, which of the following is procedures is NOT an approved technique for system cleanup after a burnout? - flushing with liquid refrigerant to clean tubing - โโ When using nitrogen to pressurize a system, you should always: - charge though a pressure regulator. - โโ What effects can ozone depletion have on the environment? - reduced crop yields; reduced marine life; increased ground-level ozone - โโ Non-azeotropic refrigerants leak from a system: - in uneven amounts due to different vapor pressures. - โโ An example of an HCFC is: - R- 22 - โโ Which chemicals are controlled by the Montreal Protocol? - chlorofluorocarbons, hydrochlorofluorocarbons, halons - โโ Systems charged with R-134a should be leak checked with: - pressurized nitrogen. - โโ When evacuating a system, the hoses should be: - equal to or larger than vacuum pump inlet connection. - โโ It has been illegal to vent substitutes for CFC and HCFC refrigerants since: - November 1995 - โโ
HFC refrigerants contain: - hydrogen, fluorine, carbon - โโ Which refrigerant contains an HCFC? - R- 22 - โโ Recovery equipment that relies upon the pressure of the refrigerant in the appliance would be considered: - System-dependent - โโ Refrigerant that enters the compressor, under normal operating conditions, is a: - low pressure vapor. - โโ It is necessary to place a refrigerant label on: - a refrigerant cylinder which is being returned for reclaiming. - โโ Which refrigerant contains a CFC? - R- 500 - โโ Use________ to remove ice from a sight glass. - an alcohol spray. - โโ According to the EPA, an oil sample should be taken for which of the following reasons? - They system had a leak or a major component failure. - โโ The EPA requires the installation of a service aperture or process stub on all appliances using a class I or class II substance as a refrigerant. The main purpose of this requirement is to make it easier to: - recover refrigerant. - โโ Recycling and recovery equipment intended for use with air-conditioning and refrigeration equipment(except for small appliances) must be tested under: - ARI 740 - โโ Refrigerant entering the compressor of a refrigeration system is a: - superheated vapor. - โโ What is being done in the U.S. to stop damage to the stratospheric ozone layer? - capturing and ultimately eliminating use of chlorofluorocarbons. - โโ
They type of oil that is most commonly used in stationary refrigeration applications with HFC-134a refrigerant is: - ester oil. - โโ The term used to describe the fact that a refrigerant blend has a range of boiling or condensing pints at a constant pressure is: - temperature glide. - โโ Which refrigerant contains a CFC? - R- 12 - โโ Under EPA's regulations, what standard must reclaimed refrigerant meet before it can be resold? - ARI 700 - โโ An example of a HFC refrigerant is: - R-134a - โโ It is illegal to: - knowingly release any refrigerant during the service, maintenance, repair or disposal of appliances, with the exception of de minimis releases. - โโ Which type of refrigerant is the most harmful to stratospheric ozone? - CFC - โโ Refrigerant that enters the expansion or throttling device (also known as the metering device) is a: - liquid. - โโ Which of the following statements would be considered good service practices for conserving refrigerant? - recover or recycle refrigerant; keep systems tight; find and repair leaks - โโ Under the EPA "safe disposal requirements", the person responsible for making sure that the refrigerant has been removed from household refrigerators before they are disposed of is the: - final person in the disposal chain - โโ Which refrigerant listed below is a "low-pressure refrigerant" under EPA's refrigerant recycling regulations? - R- 123 - โโ
Measuring the system's final vacuum is always done with: - the system isolated and the vacuum pump off. - โโ A refillable refrigerant cylinder must never be filled to more than_________ of its capacity by weight: - 80% - โโ Of the refrigerants listed below, which refrigerant type have the highest ozone depletion potential? - CFCs - โโ This chemical was found in the upper stratosphere and that indicates that the ozone layer is being destroyed. - chlorine monoxide - โโ What factor(s) affects the speed of evacuation? - the size of the equipment being evacuated; the ambient temperature; the amount of moisture in the system - โโ HCFC refrigerants contain: - hydrogen, chlorine, fluorine, carbon - โโ When a system will not hold vacuum after is has been evacuated, then: - they system may be leaking. - โโ All recovery equipment currently being made is required to have: - an EPA approved certification label. - โโ The color code for approved refrigerant recovery cylinders is______. - yellow tops and gray bodies - โโ When can you use a disposable cylinder to recover refrigerant? - never - โโ Which of the following is a "high-pressure refrigerant" under EPA's refrigerant recycling regulations? - R- 22 - โโ
After refrigerant liquid transfer between recovery unit and the system being emptied, you need to avoid trapping: - liquid refrigerant between service valves. - โโ You can determine safe pressure for leak testing a system from the: - low-side test-pressure data-plate value. - โโ If a technician has a system where some R-502 was added to an R-22 system. The technician should: - recover all the refrigerant into a separate tank. - โโ Ozone in the stratosphere above the earth consists of: - molecules of 3 oxygen atoms. - โโ The size (capacity) of the vacuum pump and the size of the suction line used will determine: - the length of dehydration time. - โโ According to the EPA, when dealing with customer complaints regarding additional costs due to refrigerant recovery efforts, the technician should: - explain the refrigerant recovery is necessary to protect human health and the environment; explain that refrigerant recovery is required by the Federal(and in some cases state and local)laws; inform the customer that professional service personnel are duty bound to follow the law and to protect the environment - โโ State and local governments can make state laws that: - follow the Clean Air Act/EPA regulations; contain stricter regulations than the Clean Air Act/EPA regulations. - โโ If an oil is hygroscopic it means that it: - readily absorbs moisture. - โโ When dehydrating a system, the system can be heated to: - decrease the dehydration time. - โโ The synthetic lubricant presently used with ternary blends containing HCFCs is: - alkylbenzene - โโ Ozone depletion in the stratosphere is what type of problem? - GLOBAL - โโ
