Earth’s atmosphere comprises of mainly Troposphere and Stratosphere.  Troposphere is the lower atmosphere extends up to 9 miles. Stratosphere extends approximately 30 miles from earth’s surface

About 15 to 18% stratosphere chlorine is contributed by natural sources (methyl chloride or HCl). Approximately about 82% of chlorine at stratosphere is contributed by ozone depletion substances (CFCs & HCFCs)

Ultrasonic leak tester made of electronics can able to filter the low frequency noise and reveal high frequency sound associated with gas leak

Dry nitrogen can be used as temperature variation under pressurization will be low. If any electronic leak detector is used a small amount of HFC gas can be added to dry nitrogen gas for determining the leak

As the refrigerant vapour is warmer, gas becomes more denser. This helps in faster recovery

Recycle refrigerant can be used for immediate use. Recycling is  a process of extracting refrigerant and cleaning the refrigerant for reuse without meeting all the purity standards envisaged by reclaiming refrigerant

Compound gauge will be on left side of the gauge manifold colour coded blue, used on the low pressure side of the system.

Temperature at which the refrigerant starts to evaporate is called bubble point. Temperature at which the last bit of refrigerant evaporates is called dew point

Clean air act is US Federal Law designed to reduce air pollution.

CFCs & HCFCs contain Chlorine & Fluorine atoms. When interacting with Sun’s UV radiation chlorine ion is separated from the CFC or HCFC molecule. Therefore the amount of chlorine formed can be determined by presence of fluorine in the Stratosphere

The inlet to the compressor is called suction line. Suction line brings low pressure vapour into the compressor.

In a refrigeration cycle, condenser will be high pressure side and evaporator is at low pressure side