What Is Fire Safe Valve?
A fire safe valve is a valve designed to maintain a minimum level of sealing and structural integrity after exposure to fire. It incorporates a secondary metal-to-metal seal behind the primary soft seat. If the soft seat melts or burns in a fire, the metal backup seal engages to limit leakage to an acceptable rate.
When Fire Safe Is Specified
Fire safe certification is mandatory for ball valves, butterfly valves, and plug valves in hydrocarbon service across virtually all oil and gas projects. Most operator and EPC specifications (Shell DEP, Saudi Aramco SAES, ADNOC) require API 607 certification for all quarter-turn valves handling flammable fluids, regardless of size or pressure class.
How Fire Safe Design Works
Standard soft-seated ball valves and butterfly valves use PTFE, PEEK, or elastomer seats that provide bubble-tight sealing under normal conditions. In a fire, these seats melt or burn within minutes, potentially releasing flammable fluids that feed the fire.
A fire safe valve incorporates a secondary metal seal behind the soft seat. When the soft seat is destroyed by fire, the metal seal engages to limit leakage to an acceptable rate. The valve also includes:
- Anti-static device: ensures electrical continuity between ball, stem, and body to dissipate static charges
- Fire-safe stem seal: graphite packing or metal-to-metal bonnet seal that survives after standard packing burns
- Body cavity relief: prevents pressure buildup from thermal expansion of trapped fluid
API 607 Fire Test
| Parameter | API 607 (7th Edition) Requirement |
|---|---|
| Valve types tested | Quarter-turn (ball, plug, butterfly) |
| Fire exposure | 750-1000 degC for 30 minutes |
| Medium | Water (upstream), air (leakage measurement) |
| Allowable seat leakage (during fire) | Limited rate per valve size (defined in standard) |
| Allowable external leakage | Limited rate per valve size |
| Post-fire operation | Valve must operate (open/close) after fire |
| Post-fire seat leakage | Must meet specified limits after cooling |
| Stem/packing leakage | Must not exceed limits during or after fire |
Fire Safe Standards Comparison
| Standard | Scope | Key Difference |
|---|---|---|
| API 607 | Quarter-turn valves (ball, plug, butterfly) | Type test (one sample represents design family) |
| API 6FA | Pipeline valves (API 6D) | More stringent, pipeline-specific requirements |
| BS 6755 Part 2 | All valve types | British standard, broadly equivalent to API 607 |
| EN ISO 10497 | All valve types | International standard, harmonized with BS 6755 |
When Fire Safe Is Required
Fire safe valves are mandatory in:
- Hydrocarbon process piping (refineries, gas plants, petrochemical)
- Pipeline block valves in populated areas
- Emergency shutdown (ESD) valve systems
- Offshore platform piping
- Fuel gas systems
- Any service where valve failure during fire would escalate the event
Most project specifications (Shell DEP, Saudi Aramco, ADNOC) require API 607 fire safe certification for all ball and butterfly valves in hydrocarbon service, regardless of size or pressure class.
Fire safe certification applies to the valve design, not individual valves. Once a valve design passes the API 607 test, all valves of that design family are certified without individual fire testing.
For valve body and trim materials, see the valve materials guide. For seat material selection (soft vs metal), see metal seat vs soft seat valves.
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