Which of the following is NOT a characteristic of A1 classification refrigerants?

In the context of refrigerants classified as A1, it is important to understand the characteristics that define this classification. A1 refrigerants are non-toxic and have low flammability, making them safe for use in various applications without posing significant health risks in case of a leak. This low toxicity is a crucial aspect, ensuring that they do not harm human health or the environment when used properly.

The term "low flammability" is indicative of A1 refrigerants, which do not ignite easily and have a low risk of causing fire hazards. Additionally, many A1 refrigerants have a low environmental impact, often contributing to lower global warming potential and ozone depletion potential compared to other classifications of refrigerants.

In this scenario, "High flammability" would be contradictory to the A1 classification, as these refrigerants are specifically chosen for their safety features, reducing the likelihood of fire-related incidents. Hence, the correct answer clearly identifies an aspect that does not belong to the A1 classification attributes.