MACS 609 Certification Practice Exam

Which item is not included in the SAE J2099 Standard of refrigerant purity?

1. Moisture

2. Sludge

3. Acidity

4. Other contaminants

The correct answer is: Sludge

The SAE J2099 Standard specifies criteria for the purity of refrigerants used in automotive air conditioning systems. One of the key aspects of this standard is to ensure that the refrigerants are free from elements that could negatively affect the performance and safety of the system. In terms of purity, moisture is critical because it can lead to the formation of acids and ice within the system, potentially causing severe damage. Acidity is another important factor because acidic refrigerants can corrode components, leading to leaks and malfunctions. Additionally, the presence of other contaminants, such as oil residue and various particulates, can impair the performance of the refrigeration cycle and damage components. Sludge, while a potential issue in other contexts, is not specifically addressed in the SAE J2099 Standard for refrigerant purity. Instead, the standard focuses on moisture, acidity, and other specific contaminants that directly impact the functionality and reliability of refrigerants in automotive systems. Therefore, sludge does not fit the primary concerns outlined in the standard, making it the correct choice as the item not included in the SAE J2099 Standard of refrigerant purity.