Final answer:
Refrigeration systems using R-410a should be leak checked with nitrogen-based tracer gas or a suitable electronic leak detector. R-410a is an HFC, which necessitates specific leak detection methods. The push for safer refrigerants like R-410a is part of a larger trend to replace hazardous substances like carbon tetrachloride.
Step-by-step explanation:
Systems charged with R-410a should be leak checked with a nitrogen-based tracer gas or an electronic leak detector specifically designed for HFC refrigerants. R-410a is a hydrofluorocarbon (HFC), which is used as a replacement for older refrigerants that have a higher ozone depletion potential. When checking for leaks, it is crucial to use methods that are compatible with HFCs to prevent false readings and potential damage to the system. Some legacy methods, like soap bubble tests, can still be used but they might not be as effective for smaller leaks that can be detected with more advanced electronic leak detectors.
As the industry progresses, older substances such as carbon tetrachloride (CC), which is toxic and carcinogenic, are being replaced with safer agents like dichloromethane (CH2Cl2) as a solvent. Similarly, HFC-134a and HCFC-141b are among the compounds that serve as substitutes for more harmful substances in various applications, including refrigerants.