A2L-Refrigerant Tips and Techniques
Questions and All Correct Answers
2025-2026 Updated.
Section 608 Certification - Answer Allows tech/engineer to purchase or handle controlled
refrigerants.
Responsibilities of tech with 608 cert - Answer Keep up with EPA regulations and if you loose
cert card get a replacement from company that provided cert
What molecules are present in the ozone in the stratosphere above earth - Answer O_3
What oxygen molecule do we breathe - Answer O_2
What does the ozone layer consist of - Answer Ozone in the stratosphere at an altitude of
between 7 and 28 miles above earth
What is the ozone layer formed by and what does it do? - Answer Formed by UV light from
the sun acting on oxygen molecules and it absorbs and scatters the UV sunlight preventing
harmful amounts of UV light from reaching earth. Also referred to as ozone shield
What causes ozone in the lower atmosphere? - Answer UV acting on smog and air
pollutants... the effect is a harmful pollutant as opposed to a protective shield when ozone
remains in the stratosphere
What is Ozone depletion potential (ODP) - Answer The ability of a substance to destroy
ozone in the stratosphere
Why do refrigerants cause ozone depletion - Answer The chlorine in them
How many ozone molecules are destroyed by each chlorine atom in stratosphere - Answer
100,000 ozone molecules
What is the result of ozone depletion - Answer More UV radiation penetrates to earths
surface
How do we know chlorine rises in the stratosphere is not from natural sources - Answer Rise
in chlorine matches rise in emissions of CFCs and HCFCs and the rise in the fluorine in the
,stratosphere which suggests rise in chlorine is primarily coming from unnatural sources (man
made)
Do volcanoes contribute to chlorine in stratosphere - Answer Only a small anount
What makes stratospheric ozone protection uniquely important compared to other
environmental issues - Answer It is a global issue
What is the Montreal Protocol - Answer An international treaty designed to protect the
ozone layer by limiting ozone depleting substances
What other than chlorine causes ozone depletion - Answer Bromine
What are possible results of damage to the ozone layer - Answer Skin cancer, cataracts,
suppression of immune system, reduced crop yields, damage to marine life, increased
degradation of polymers, and climate change
What is the SNAP program - Answer The significant new alternatives policy program
identifies refrigerants with lower overall risks to human health and the environment.
What is the clear air act - Answer Establishes that knowingly releasing refrigerants during
service, repair, maintenance, or disposal of appliances is illegal. Punishable by fines of up to
$44,539 per day, loss of certification, and federal charges. State laws maybe even more strict
What are CFCs - Answer Chlorofluorocarbons which contain elements chlorine, fluorine, and
carbon
What refrigerants have the highest ODP - Answer CFCs have highest ozone depletion
potential and are most harmful to the stratospheric ozone
What makes CFCs stable and what makes them damaging to the ozone layer - Answer They
don't contain hydrogen, and they do contain chlorine respectively
Why are CFCs able to reach the stratosphere - Answer They are stable and don't dissolve in
water meaning they can't be removed by rain
What two CFCs were commonly used before being banned - Answer R-11, and R-12
, Are CFCs still used? Why? - Answer No they were phased out to stop damage to the
stratospheric ozone layer
HCFCs - Answer Hydrochlorofluorocarbons are a group of chemicals used to replace CFCs
containing hydrogen, chlorine, fluorine, and carbon
Characteristics of HCFCs - Answer Stable, and don't dissolve or breakdown in water therefore
they can also reach stratosphere. Air samples have shown this
Why are HCFCs better than CFCs? - Answer They are less stable and therefore decompose
faster and are less damaging to the ozone
List HCFCs - Answer R-22, R-123, R-124
Are HCFCs still used - Answer No they were phased out to stop damage to stratospheric
ozons
HFCs - Answer hydrofluorocarbons, contain hydrogen, fluorine, and carbon
Do HFCs cause ODP - Answer No because there is no chlorine
What are the hazards of HFCs - Answer They have global warming potential (GWP) that is
thousands of times greater than hydrocarbon (HC) refrigerants and CO2. They can't be vented
on
List HFCs - Answer R-134a, R-404A, R-407C, and R410A
HFOs - Answer Hydrofluoroolefin refrigerants have zero ODP and low GWP. Contain
hydrogen, fluorine, and carbon but are unsaturated
The AsHRAE safety group classification system classifies some HFOs like R-1234yf as... - Answer
A2L- non toxic (A) and slightly flammable (2L). Not all HFO's are flammable
Are HFOs or HC refrigerants less flammable - Answer HFOs (2L vs 3) because they contain
fluorine
What is not compatible with HFO - Answer Silicone
Questions and All Correct Answers
2025-2026 Updated.
Section 608 Certification - Answer Allows tech/engineer to purchase or handle controlled
refrigerants.
Responsibilities of tech with 608 cert - Answer Keep up with EPA regulations and if you loose
cert card get a replacement from company that provided cert
What molecules are present in the ozone in the stratosphere above earth - Answer O_3
What oxygen molecule do we breathe - Answer O_2
What does the ozone layer consist of - Answer Ozone in the stratosphere at an altitude of
between 7 and 28 miles above earth
What is the ozone layer formed by and what does it do? - Answer Formed by UV light from
the sun acting on oxygen molecules and it absorbs and scatters the UV sunlight preventing
harmful amounts of UV light from reaching earth. Also referred to as ozone shield
What causes ozone in the lower atmosphere? - Answer UV acting on smog and air
pollutants... the effect is a harmful pollutant as opposed to a protective shield when ozone
remains in the stratosphere
What is Ozone depletion potential (ODP) - Answer The ability of a substance to destroy
ozone in the stratosphere
Why do refrigerants cause ozone depletion - Answer The chlorine in them
How many ozone molecules are destroyed by each chlorine atom in stratosphere - Answer
100,000 ozone molecules
What is the result of ozone depletion - Answer More UV radiation penetrates to earths
surface
How do we know chlorine rises in the stratosphere is not from natural sources - Answer Rise
in chlorine matches rise in emissions of CFCs and HCFCs and the rise in the fluorine in the
,stratosphere which suggests rise in chlorine is primarily coming from unnatural sources (man
made)
Do volcanoes contribute to chlorine in stratosphere - Answer Only a small anount
What makes stratospheric ozone protection uniquely important compared to other
environmental issues - Answer It is a global issue
What is the Montreal Protocol - Answer An international treaty designed to protect the
ozone layer by limiting ozone depleting substances
What other than chlorine causes ozone depletion - Answer Bromine
What are possible results of damage to the ozone layer - Answer Skin cancer, cataracts,
suppression of immune system, reduced crop yields, damage to marine life, increased
degradation of polymers, and climate change
What is the SNAP program - Answer The significant new alternatives policy program
identifies refrigerants with lower overall risks to human health and the environment.
What is the clear air act - Answer Establishes that knowingly releasing refrigerants during
service, repair, maintenance, or disposal of appliances is illegal. Punishable by fines of up to
$44,539 per day, loss of certification, and federal charges. State laws maybe even more strict
What are CFCs - Answer Chlorofluorocarbons which contain elements chlorine, fluorine, and
carbon
What refrigerants have the highest ODP - Answer CFCs have highest ozone depletion
potential and are most harmful to the stratospheric ozone
What makes CFCs stable and what makes them damaging to the ozone layer - Answer They
don't contain hydrogen, and they do contain chlorine respectively
Why are CFCs able to reach the stratosphere - Answer They are stable and don't dissolve in
water meaning they can't be removed by rain
What two CFCs were commonly used before being banned - Answer R-11, and R-12
, Are CFCs still used? Why? - Answer No they were phased out to stop damage to the
stratospheric ozone layer
HCFCs - Answer Hydrochlorofluorocarbons are a group of chemicals used to replace CFCs
containing hydrogen, chlorine, fluorine, and carbon
Characteristics of HCFCs - Answer Stable, and don't dissolve or breakdown in water therefore
they can also reach stratosphere. Air samples have shown this
Why are HCFCs better than CFCs? - Answer They are less stable and therefore decompose
faster and are less damaging to the ozone
List HCFCs - Answer R-22, R-123, R-124
Are HCFCs still used - Answer No they were phased out to stop damage to stratospheric
ozons
HFCs - Answer hydrofluorocarbons, contain hydrogen, fluorine, and carbon
Do HFCs cause ODP - Answer No because there is no chlorine
What are the hazards of HFCs - Answer They have global warming potential (GWP) that is
thousands of times greater than hydrocarbon (HC) refrigerants and CO2. They can't be vented
on
List HFCs - Answer R-134a, R-404A, R-407C, and R410A
HFOs - Answer Hydrofluoroolefin refrigerants have zero ODP and low GWP. Contain
hydrogen, fluorine, and carbon but are unsaturated
The AsHRAE safety group classification system classifies some HFOs like R-1234yf as... - Answer
A2L- non toxic (A) and slightly flammable (2L). Not all HFO's are flammable
Are HFOs or HC refrigerants less flammable - Answer HFOs (2L vs 3) because they contain
fluorine
What is not compatible with HFO - Answer Silicone
