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[Audio] This instruction was given by a teacher to her students. She wanted them to provide clear and concise answers to their questions, avoiding unnecessary words or phrases that could confuse others. The teacher emphasized that this approach would help students develop good writing skills and improve their ability to communicate effectively. She also pointed out that using simple language and avoiding jargon or technical terms would make it easier for others to understand their responses. By following these guidelines, students can produce high-quality written work that is easy to read and comprehend..

[Audio] The refrigerant gases are divided into three categories: non-azeotropic, azeotropic, and zeotropic. Non-azeotropic refrigerants have no fixed boiling point and can be used for various applications such as cooling systems, air conditioning systems, and refrigeration systems. Azeotropic refrigerants have a fixed boiling point and are typically used for specific applications such as refrigeration systems and air conditioning systems. Zeotropic refrigerants have a fixed boiling point and are typically used for specific applications such as refrigeration systems and air conditioning systems. However, zeotropic refrigerants are more commonly used than azeotropic refrigerants due to their higher efficiency and lower cost..

[Audio] We are now going to discuss the various refrigerant gases that have a very low climate impact. This is an important aspect to consider when selecting a refrigerant gas for use in industrial or commercial applications. The table below provides information on the refrigerants with very low climate impact, including their chemical names, global warming potential, and status of use. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We will now discuss the data presented in the table. As we can see, the refrigerant gases with very low climate impact have varying levels of global warming potential, ranging from 0.02 to 1.81. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We are now going to discuss the various refrigerant gases that have a very low climate impact. This is an important aspect to consider when selecting a refrigerant gas for use in industrial or commercial applications. The table below provides information on the refrigerants with very low climate impact, including their chemical names, global warming potential, and status of use. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We will now discuss the data presented in the table. As we can see, the refrigerant gases with very low climate impact have varying levels of global warming potential, ranging from 0.02 to 1.81. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We are now going to discuss the various refrigerant gases that have a very low climate impact. This is an important aspect to consider when selecting a refrigerant gas for use in industrial or commercial applications. The table below provides information on the refrigerants with very low climate impact, including their chemical names, global warming potential, and status of use. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We will now discuss the data presented in the table. As we can see, the refrigerant gases with very low climate impact have varying levels of global warming potential, ranging from 0.02 to 1.81. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We are now going to discuss the various refrigerant gases that have a very low climate impact. This is an important aspect to consider when selecting a refrigerant gas for use in industrial or commercial applications. The table below provides information on the refrigerants with very low climate impact, including their chemical names, global warming potential, and status of use. We will review each of these refrigerants in more detail, including their applications, toxicity, and flammability. This will help us to make informed decisions when selecting a refrigerant gas for our needs. We will now discuss the data presented in the table. As we can see, the refrigerant gases with very low climate impact have varying levels of global warming potential, ranging from 0.02 to 1.81..

[Audio] The widely used HFC refrigerants are listed in the table below. The table includes the following information: refrigerant code, chemical name, global warming potential over 20 years, global warming potential over 100 years, status, applications, toxicity/flammability, normal suction pressure, normal discharge pressure, standing pressure, power consumption, and alternative. R-32, also known as HFC-32, difluoromethane, has a global warming potential of 2690 over 20 years and 771 over 100 years. It is widely used in residential and commercial air conditioners and heat pumps. It is classified as Class A2L, which means it is low in toxicity and flammability. The normal suction pressure is between 120 and 140 psig, and the normal discharge pressure is between 380 and 450 psig. The power consumption is around 0.29 kilowatts per kilowatt of refrigeration. R-454B is a mixture of R-32 and R-1234yf, with a global warming potential of 1806 over 20 years and 516 over 100 years. It is used in residential and light commercial air conditioning systems, heat pumps, and small chillers. It is also classified as Class A2L, low in toxicity and flammability. The normal suction pressure is around 114 psig, and the normal discharge pressure is around 349 psig. The power consumption is around 0.33 kilowatts per kilowatt of refrigeration. R-513A is a mixture of R-1234yf and R-134a, with a global warming potential of 1788 over 20 years and 647 over 100 years. It is used in chillers, heat pumps, and ice rinks. It is classified as Class A1, non-flammable and non-toxic. The normal suction pressure is between 15 and 30 psig, and the normal discharge pressure is between 120 and 180 psig. The power consumption is around 0.32 kilowatts per kilowatt of refrigeration..

[Audio] ## Step 1: Identify the main purpose of the text The main purpose of the text is to inform readers about the properties and uses of various refrigerants. ## Step 2: Determine the key points to be included in the rewritten text Key points include providing information on refrigerant codes, characteristics, and alternatives; highlighting global warming potential (GWP), toxicity, flammability, and other relevant factors; and discussing the importance of selecting the right refrigerant for specific applications. ## Step 3: Rewrite the text in full sentences only Refrigerant codes provide details about the properties and uses of these substances. Different refrigerants have distinct characteristics and alternatives. The table lists various refrigerants along with their characteristics and alternatives. The data includes information on global warming potential (GWP), toxicity, flammability, and other factors. Refrigerants have diverse applications, including gas dusters, low-pressure chillers, and commercial and industrial applications. Some refrigerants, such as R-123, are being phased out due to health concerns. Other refrigerants, like HFC-152a, are being phased out due to environmental concerns. Selecting the right refrigerant is crucial, considering factors like toxicity, flammability, and GWP. ## Step 4: Ensure that all sentences are complete and make sense on their own All sentences should convey a clear idea or message without needing additional context. ## Step 5: Review the rewritten text for clarity and coherence The rewritten text should clearly communicate the importance of selecting the right refrigerant based on its characteristics and the need to consider factors like GWP, toxicity, and flammability. The final answer is:.

[Audio] The speaker explains that when using toxic refrigerants such as R-717, proper safety precautions are necessary in unventilated spaces. Similarly, when using flammable refrigerants like R-290, special precautions are required. The speaker highlights the importance of considering hazard categories according to ASHRAE 34 and ISO 817 standards. The hazards in different spaces, such as unventilated enclosed spaces and ventilated but explosive-prone environments, need to be addressed separately. The speaker emphasizes the need for design and installation of ventilation systems, emergency purge/exhaust systems, gas detection and alarms, and other safety measures to mitigate these risks..

[Audio] The importance of operational safety cannot be overstated when it comes to handling refrigerants. Ensuring that only trained and certified personnel handle refrigerants is crucial. Leak checking before charging refrigerants is also vital. Never overcharging systems is another critical aspect. Workers must be trained in first aid for exposure to refrigerants, such as ammonia inhalation or CO2 asphyxiation. Key standards to follow include ASHRAE Standard 15, EN 378, NFPA 70, NFPA 55/NFPA 90A, and OSHA 1910.146. These standards provide essential guidelines for maintaining a safe working environment when dealing with refrigerants. Adhering to these standards minimizes risks associated with refrigerant handling and ensures a safer workplace..

[Audio] The Refrigerant Safety Risk Matrix provides a comprehensive overview of the hazards associated with different refrigerant types in various environments. This matrix highlights the main hazards, necessary precautions, and controls required for each type of refrigerant. The matrix categorizes refrigerants into three groups: flammable, toxic, and asphyxiant, each with its unique set of risks and mitigation strategies. By understanding this matrix, users can take appropriate measures to ensure their safety while handling refrigerants..

[Audio] The refrigeration system uses a refrigerant gas that changes its state from liquid to gas as it absorbs heat from the surrounding environment. The refrigerant gas is contained within a sealed vessel called a compressor, which compresses the gas to increase its temperature. The compressed gas then enters a condenser where it releases its heat to the surroundings and cools down. The cooled gas then enters an expansion valve, which reduces its pressure and allows it to expand into a low-pressure area. This expansion causes the gas to cool further and eventually return to its liquid state. The process is repeated continuously until the desired temperature is reached. The refrigerant gas is typically used in air conditioning systems, refrigerators, and freezers..