A2L Properties and Classification 2

Question 1

What does the 'A2L' classification mean in the ASHRAE 34 safety classification system?

Accepted Answer

Lower toxicity (A), lower flammability (2), with low burning velocity (L)

Answer

Class A toxicity, Class 2 flammability, L = liquid state

Answer

Approved for 2 liters maximum charge

Answer

Advanced 2nd generation, low-cost

Question 2

What is the Global Warming Potential (GWP) advantage of A2L refrigerants over R-410A?

Accepted Answer

A2L alternatives typically have GWP 1/3 to 1/4 of R-410A's GWP of 2088

Answer

A2L refrigerants have higher GWP

Answer

There is no GWP difference

Answer

A2L refrigerants have zero GWP

Question 3

How does the burning velocity of A2L refrigerants compare to common flammable gases like propane?

Accepted Answer

A2L refrigerants burn at less than 10 cm/s — roughly 1/4 the speed of propane

Answer

A2L refrigerants burn faster than propane

Answer

They burn at the same speed

Answer

A2L refrigerants don't burn at all

Question 4

What is the minimum ignition energy (MIE) for most A2L refrigerants and why does it matter?

Accepted Answer

Relatively high — typically 100-1000+ millijoules, much higher than common flammable gases

Answer

Very low — similar to gasoline vapor

Answer

Zero — they ignite spontaneously

Answer

The same as all other refrigerants

Question 5

Which common A2L refrigerant is a single-component (non-blended) refrigerant?

Accepted Answer

R-32

Answer

R-454B

Answer

R-407C

Answer

R-404A

Question 6

At what approximate temperature range do most A2L refrigerants auto-ignite?

Accepted Answer

500-750°C

Answer

Room temperature (20-25°C)

Answer

100-200°C

Answer

Above 1000°C