Refrigerants play a critical role in air conditioning and refrigeration systems, but their safety varies depending on two key factors: toxicity and flammability. To ensure safe usage, refrigerants are classified into safety categories, making it easier to assess their risks.
The classification system is outlined in the national standard GB/T 7778-2017 titled “Refrigerant Numbering and Safety Classification Method.” It divides refrigerants into groups based on:
- Toxicity: The long-term health risk of exposure to the refrigerant.
- Class A: Low chronic toxicity.
- Class B: High chronic toxicity.
- Flammability: The refrigerant’s potential to ignite or explode.
- Class 1: No flame propagation (non-flammable).
- Class 2L: Lower flammability.
- Class 2: Flammable.
- Class 3: Highly flammable and explosive.
Refrigerant Safety Levels
By combining toxicity (A or B) and flammability (1, 2L, 2, or 3), refrigerants are grouped into eight safety levels:
Common Refrigerants by Safety Class
Here’s where popular refrigerants fall within these categories:
A1: Safest and Widely Used
- Examples: R22, R410A, R134a, R407C, R508A
- Characteristics: Non-flammable and low toxicity, making them ideal for most applications.
A2L: Low Global Warming Potential, Slightly Flammable
- Examples: R32, R1234yf
- Characteristics: Mildly flammable but environmentally friendly with lower global warming potential (GWP).
A2: Flammable but Lower Toxicity
- Examples: R142b, R152a
- Characteristics: Flammable but less commonly used compared to A1 or A2L refrigerants.
A3: Highly Flammable, Mostly Natural Refrigerants
- Examples: R290 (propane), R600a (isobutane)
- Characteristics: Often used in specific applications like small refrigeration units due to their high flammability.
B1: Non-Flammable but High Toxicity
- Examples: R123, R245fa
- Characteristics: Used in specialized applications but with caution due to toxicity.
B2L: Slightly Flammable and Toxic
- Example: R717 (ammonia)
- Characteristics: Common in industrial settings with proper safeguards.
B2 and B3: Dangerous and Rarely Used
- Characteristics: Due to high toxicity and flammability, these refrigerants require stringent safety measures.
What Does This Mean for You?
When choosing or upgrading your HVAC system, it’s essential to consider the refrigerant’s safety classification. Systems using A1 or A2L refrigerants are often preferred for their balance of safety and environmental benefits. However, more flammable refrigerants, like those in Class A3, require specialized systems and careful handling.
At Aether HVAC, we ensure that all refrigerants we use meet industry safety standards and are installed with the highest precautions. Contact us today to learn more about refrigerants and how we prioritize your safety and comfort.
