What is ODP? Why is it important in choosing a fire extinguishing agent?
If you have been choosing a fire extinguishing agent, and particularly a clean agent, you have probably seen ODP on a technical data sheet without being told what it means or why it matters to a fire suppression system.
ODP, or ozone depletion potential, compares how much a chemical can deplete ozone in the atmosphere against the reference substance CFC-11, which is set at an ODP of 1.0.
It matters a great deal in fire protection, because agents such as Halon were once widely used, put fires out very effectively, and damaged the ozone layer while doing it. That is what drove the industry toward alternatives with ODP = 0.
One of the agent groups drawing attention today is FK-5-1-12, which has ODP = 0 and is used in clean agent systems, including products such as the PAF-222 clean agent fire extinguisher.
What does ODP stand for?
ODP = Ozone Depletion Potential
The potential to deplete the ozone layer.
It compares the impact of a chemical on atmospheric ozone, using CFC-11 as the reference and setting CFC-11 at ODP = 1.0.
So in principle, ODP = 1 means an ozone depletion potential equivalent to CFC-11 under that evaluation framework.
ODP = 0 means no ozone depletion potential under that same method.
What is the ozone layer and why does it matter?
The ozone layer sits in the stratosphere and does the work of absorbing ultraviolet, or UV, radiation from the sun.
If it thins, more UV-B radiation reaches the Earth's surface, which can affect:
Human health
Ecosystems
Agricultural crops
Marine life
The environment as a whole
Ozone-depleting substances (ODS) are therefore controlled internationally through the Montreal Protocol, and by domestic law in individual countries.
How does ODP work?
Substances that can deplete ozone usually contain chlorine or bromine.
Some are stable in the lower atmosphere but travel up to the stratosphere. There, high energy UV radiation breaks the molecules apart and releases chlorine or bromine atoms.
Those atoms take part in reactions that destroy ozone molecules, and the cycle can repeat many times over.
That is why some older agents, Halon among them, carry environmental problems despite being highly effective at putting fires out.
Why does the ODP of a fire extinguishing agent matter?
Judged on suppression performance alone, an agent might be excellent.
But choosing an agent today is no longer just a question of:
"Will it put the fire out?"
You also have to ask:
Does it affect the ozone layer?
What is its ODP?
What is its GWP? (Read more at What is GWP)
How does it affect the people using it? (See how to verify this from documents at What is a carcinogen-free fire extinguishing agent)
Does it affect the equipment? (See non-conductive properties at What is non-conductive (Dielectric))
Does it carry standards and certifications? (Read more at What are the certifications of PAF-222)
Can you source it in the long term?
ODP is one of the environmental indicators worth weighing when you choose an agent.
Halon and ODP: why was Halon replaced?
Halon is a highly effective agent and was once used everywhere, particularly where a fire had to be put out fast and without residue.
But its ODP is high.
The EPA states that Halon can reach an ODP as high as 10 depending on the type, against CFC-11 at ODP = 1.0 as the reference.
Halon 1211, for example, sits at roughly 3 according to EPA data, and some other types run much higher.
That put Halon among the substances controlled under the ozone protection framework, and drove the development of alternative technologies. The FK-5-1-12 group is one of them.
To see how the agent types differ, read more at What is the difference between clean agents and dry chemical powders.
So what is the ODP of HFC-227ea?
This is where it gets important.
HFC-227ea, the agent behind the products widely known as FM-200, has ODP = 0.
The EPA lists HFC-227ea at ODP = 0 but with a GWP of approximately 3,220.
HFCs have ODP = 0 because they contain no chlorine in their molecular structure, unlike CFCs and HCFCs, which can contribute to ozone depletion.
Which raises the point that matters:
ODP = 0 does not mean a substance has no environmental impact at all.
GWP still has to be considered. Read more at What is GWP
Comparing the ODP of fire extinguishing agents
Extinguishing Agent | ODP | Approximate GWP* | Agent Group |
|---|---|---|---|
Halon 1211 | 3 | 1,750 | Halon |
Halon 1301 | 10 | 6,900 – 7,430 | Halon |
HFC-227ea | 0 | 3,220 | HFC |
FK-5-1-12 | 0 | <1 | Fluorinated Ketone |
CO₂ | 0 | 1 | Carbon Dioxide |
What is the ODP of FK-5-1-12?
FK-5-1-12 has ODP = 0.
The EPA lists FK-5-1-12 in the total flooding agents group with ODP = 0 and GWP < 1 in current SNAP data.
Technical data from a number of FK-5-1-12 system manufacturers gives ODP = 0 as well.
So on ozone protection, FK-5-1-12 holds a significant advantage over the high ODP Halon agents.
That said, ODP = 0 does not answer every environmental question. PFAS is a separate matter, and one where the documents need reading carefully. Read more at What is the difference between PFAS-free and PFAS non-detected.
How is PAF-222 related to ODP?
PAF-222 is a clean agent fire extinguisher product using FK-5-1-12 as its primary agent.
So on the environmental properties of FK-5-1-12, the ODP is 0.
Which means FK-5-1-12 has no ozone depletion potential according to the ODP values used in reference data.
That is one of the reasons FK-5-1-12 is used as an alternative in new generation clean agent systems.
The EPA lists FK-5-1-12 as an acceptable alternative for total flooding systems and gives it ODP = 0.
To compare the PAF-222 clean agent fire extinguisher with the agents in common use, read more at What is the difference between PAF-222 and general fire extinguishers.
Why does ODP matter when choosing an agent for a new system?
Fire suppression systems are usually designed to run for many years.
So the choice of agent should be made with the long term in view.
1. Reduce dependence on ozone-depleting substances
Agents with a high ODP carry more environmental and regulatory restrictions.
2. Support environmental commitments
Choosing an agent with ODP = 0 gives the system better ozone protection properties. If you want to start with a portable extinguisher first, read more at Clean Agent Fire Extinguishers.
3. Reduce exposure to regulatory change
High ODP substances sit under the control frameworks for ozone-depleting substances, with the Montreal Protocol as the international mechanism regulating their production and consumption. If you run an existing HFC system, read the transition guidelines at What is the replacement for HFC-227ea and What is the replacement for Novec 1230.
4. Support decisions on new projects
If you are designing a new system, looking at ODP and GWP from the start lets you compare the options properly. For guidance on selecting equipment by area type and risk level, read more at Choosing fire protection equipment to suit your area and risk.
What to read next after understanding ODP
Now that you know what ODP is and how it shapes the choice of agent, these related topics follow on:
What is PAF-222
PAF GLOBAL's clean agent fire extinguisher product and its practical applications.What is FK5112 / What is FK-5-1-12
Agent names, properties, and basic technical terms.What is GWP
The global warming potential metric, which is always read alongside ODP.What is the difference between PFAS-free and PFAS non-detected
For anyone reading test results and documents before purchasing.What is a carcinogen-free fire extinguishing agent and how to check from SDS and Certificate
For procurement teams verifying agent safety against real documents.Choosing fire fighting equipment suitable for area and risk
For matching equipment to each area, from offices to electrical rooms, MDB cabinets and factories.What is the difference between clean agents and dry chemical powders
How clean agents differ from traditional extinguishing agents.What is the difference between PAF-222 and general fire extinguishers
For anyone comparing options before settling on an agent type.Clean Agent Fire Extinguishers
The overall picture of clean agent extinguishers and their commercial use.What is non-conductive (Dielectric)
For anyone selecting agents for electrical and electronic equipment.What is the replacement for Novec 1230
For current Novec 1230 users weighing alternatives within the FK-5-1-12 group.PAF GLOBAL: Fire Fighting Equipment Distributor in Thailand
For organizations looking for distributors and consultants in Thailand.
Frequently Asked Questions (FAQ)
1. What is ODP?
ODP stands for ozone depletion potential. It compares the impact of a substance on ozone against CFC-11, which has an ODP of 1.0.
2. What does ODP = 0 mean?
That the substance has an ozone depletion potential of zero under the evaluation method used, or no potential to deplete the ozone layer on that value.
3. What is the difference between ODP and GWP?
ODP measures the impact on the ozone layer, GWP measures global warming potential. So a substance can have ODP = 0 and still carry a high GWP, as HFC-227ea does. Read more at What is GWP.
4. Does Halon have a high ODP?
Yes. The EPA states that Halon can reach an ODP of approximately 10, depending on the type.
5. What is the ODP of HFC-227ea?
HFC-227ea has ODP = 0, but a GWP of approximately 3,220 according to EPA data for total flooding agents.
6. What is the ODP of FK-5-1-12?
FK-5-1-12 has ODP = 0, and the EPA lists a GWP of < 1 in SNAP data for total flooding agents. Read the detail on the substance at What is FK5112 / What is FK-5-1-12.
7. What is the ODP of PAF-222?
PAF-222 uses FK-5-1-12 as its main agent, so it takes the environmental properties of FK-5-1-12, which has ODP = 0.
8. Does ODP = 0 mean the substance is entirely safe for the environment?
No. ODP is only an indicator of ozone depletion. GWP, atmospheric lifetime, how the substance is managed, and other environmental factors all have to be weighed alongside it, including PFAS. Read more at What is the difference between PFAS-free and PFAS non-detected.
9. Why should a fire extinguishing agent care about ODP?
Because fire suppression systems have a service life of many years. Choosing a substance with no ozone depletion potential keeps you aligned with ozone protection and reduces reliance on ODS.
10. Should an agent be chosen on ODP alone?
No. Weigh ODP + GWP + safety + suppression performance + standards and certifications + suitability for the area + maintenance together.