1. Response to Natural Gas Fires and Emergencies Fire Engineer Scott Sanders

2. Natural Gas Fires and Emergencies Most common gas fuel in US Most common gas fuel in US More than half American homes use natural gas for heating and cooking More than half American homes use natural gas for heating and cooking Installed in 60% of new homes Installed in 60% of new homes Installed in CNG Hybrid Vehicles Installed in CNG Hybrid Vehicles Natural Gas Natural Gas Methane 70-90% Methane 70-90% Ethane Ethane Propane Propane Butane Butane Carbon Dioxide and Nitrogen Carbon Dioxide and Nitrogen

3. Natural Gas Fires and Emergencies Natural Gas Natural Gas Primary Hazard is Flammability Primary Hazard is Flammability Non-Toxic Non-Toxic Asphyxiant Asphyxiant Carbon Monoxide: Toxic Product of In-Complete Combustion Carbon Monoxide: Toxic Product of In-Complete Combustion Odorization Odorization Mercaptan Mercaptan 1/10 th of 1% air 1/10 th of 1% air Identifies gas leak long before dangerous (LEL) Identifies gas leak long before dangerous (LEL) Prolonged exposure may desensitize individuals Prolonged exposure may desensitize individuals

4. Natural Gas Fires and Emergencies Characteristics of Common Gas Fuels GasVapor DensityIgnition PointLEL Natural Gas.55-.651,000-1,200F 4% Propane 1.6842F2.1% Butane 2.0550F1.6% ALL should be considered…. Although NG is most prevalent.

5. Natural Gas Fires and Emergencies Distribution Systems Distribution Systems May be pressurized as high as 1,000 psi May be pressurized as high as 1,000 psi Williams Pipeline Williams Pipeline Atlanta Gas Light / Scana Atlanta Gas Light / Scana Similar to municipal water systems Similar to municipal water systems Consist of street mains that branch to service lines that bring gas to individual occupancies Consist of street mains that branch to service lines that bring gas to individual occupancies Regulator reduces pressure to ¼ psi Regulator reduces pressure to ¼ psi

6. Natural Gas Hazards Air in a Gas Line Air in a Gas Line Usually occurs after work has been done and air hasnt been properly bled from line. Usually occurs after work has been done and air hasnt been properly bled from line. Can also enter a gas line as a result of meter tampering. Can also enter a gas line as a result of meter tampering. Results in Air Slug Results in Air Slug

7. Natural Gas Hazards Combustion Explosion Combustion Explosion Gas leak confined to an area Gas leak confined to an area Flammable range Flammable range Ignition results in: Ignition results in: Rapid combustion or explosion Rapid combustion or explosion Air doubles in volume for every 459F of increase Air doubles in volume for every 459F of increase Air increases pressure inside building 60-110 psi Air increases pressure inside building 60-110 psi Most buildings cant withstand increase of more than 1 psi without failing Most buildings cant withstand increase of more than 1 psi without failing

8. Natural Gas Hazards Loss of Odor Loss of Odor Sand/Dirt can Scrub odorant out of gas Sand/Dirt can Scrub odorant out of gas Results in virtually undetectable gas Results in virtually undetectable gas Some companies use Odorless gas in manufacturing process Some companies use Odorless gas in manufacturing process Sensitization can result from prolonged exposure to gas and can result in miss-identification by firefighters. Sensitization can result from prolonged exposure to gas and can result in miss-identification by firefighters. Use Combustible Gas Indicator for NG emergencies Use Combustible Gas Indicator for NG emergencies

9. Natural Gas Hazards Regulator Failure Regulator Failure Strong smell of gas Strong smell of gas Hissing sound Hissing sound May lead to over-pressurization of appliances May lead to over-pressurization of appliances High Pressure Systems High Pressure Systems Vent pipe: Atmospheric Dump Vent pipe: Atmospheric Dump FD Response FD Response Control utilities Control utilities Notify Gas Supplier Notify Gas Supplier

10. Flammable Gas Fires Tactics Tactics Protect Exposures Protect Exposures # 1 Consideration after LIFE SAFETY # 1 Consideration after LIFE SAFETY May compound situation due to lack of resources May compound situation due to lack of resources Shut off gas before extinguishment Shut off gas before extinguishment May re-ignite after extinguishment in presence of ignition source May re-ignite after extinguishment in presence of ignition source If gas is confined nay result in explosion. If gas is confined nay result in explosion. Dissipate Leaking Gases Dissipate Leaking Gases Ventilate Inside and Disperse Outside Ventilate Inside and Disperse Outside Secure Ignition Sources Secure Ignition Sources Allow Gas to Vent & Burn Allow Gas to Vent & Burn Safest practice if gas cannot be secured prior to extinguishment Safest practice if gas cannot be secured prior to extinguishment

11. Indoor Gas Leaks Understand your enemy and where he lives!!! Understand your enemy and where he lives!!! Tactics for Indoor Gas Leaks Tactics for Indoor Gas Leaks Life Safety (Search) Life Safety (Search) Position Apparatus Safely Position Apparatus Safely Collapse potential Collapse potential Water Supply? Water Supply? Determine whether the report of the leak is accurate Determine whether the report of the leak is accurate When was the leak noticed? When was the leak noticed? What is involved? What is involved?

12. Indoor Gas Leaks Search the Area for Trapped Occupants Search the Area for Trapped Occupants Effects of Gas on Occupants Effects of Gas on Occupants Normal Oxygen Concentration = 21% Normal Oxygen Concentration = 21% Loss of motor coordination = 17% Loss of motor coordination = 17% Faulty judgment and fatigue = 10%-14% Faulty judgment and fatigue = 10%-14% Unconsciousness and death = 6%-10% Unconsciousness and death = 6%-10% Consider SUICIDE in some cases! Consider SUICIDE in some cases! Usually from Carbon Monoxide not Natural Gas. Usually from Carbon Monoxide not Natural Gas.

13. Indoor Gas Leaks Prevent Ignition Prevent Ignition Ignition Sources Ignition Sources Hand Light? Hand Light? Radio? Radio? SCBA Electronics? SCBA Electronics? Static Electricity? Static Electricity? Building Utilities? Building Utilities? If it is OFF, Leave it OFF! If it is OFF, Leave it OFF! Ventilate Ventilate Natural Ventilation Natural Ventilation

14. Indoor Gas Leaks Locating the leak Locating the leak Use Combustible Gas Indicator; NOT your NOSE!! Use Combustible Gas Indicator; NOT your NOSE!! 10% LEL (Methane 5%, Propane 2.1%, Butane 1.6%) 10% LEL (Methane 5%, Propane 2.1%, Butane 1.6%) Call Gas Company Call Gas Company Always report even if you stopped the leak Always report even if you stopped the leak Required to re-light pilot lights and repair system Required to re-light pilot lights and repair system

15. Indoor Gas Leaks Shut-Off Gas Shut-Off Gas Order of priority: Order of priority: Appliance Quarter-Turn Shutoff Appliance Quarter-Turn Shutoff Meter Quarter-Turn Wingcock Meter Quarter-Turn Wingcock NEVER TURN ON A GAS VALVE, SERVICE OR APPLIANCE AFTER IT HAS BEEN SHUT OFF!!!! NOTIFY GAS COMPANY!!!! NEVER TURN ON A GAS VALVE, SERVICE OR APPLIANCE AFTER IT HAS BEEN SHUT OFF!!!! NOTIFY GAS COMPANY!!!!

16. Indoor Gas Leaks Shut Off and Meter Shut Off and Meter

17. Outdoor Gas Leaks Tactics and Considerations Tactics and Considerations Determine whether a Gas Leak Exists Determine whether a Gas Leak Exists Use Meters Use Meters Consider Sewer Gas (Hydrogen Sulfide) Consider Sewer Gas (Hydrogen Sulfide) Call the Utility Company Call the Utility Company Low Pressure – FD can sometimes handle Low Pressure – FD can sometimes handle Beware of Static Hazard of Plastic Pipe Beware of Static Hazard of Plastic Pipe High Pressure – Requires Special Equipment High Pressure – Requires Special Equipment

18. Outdoor Gas Leaks Determine Scope of Incident Determine Scope of Incident Size of Line Size of Line Pressure Pressure Gas Escaping into atmosphere Gas Escaping into atmosphere Gas Escaping into Storm Drains (Buildings) Gas Escaping into Storm Drains (Buildings) Other utilities affected Other utilities affected Define Hazard Area and Protect Public Define Hazard Area and Protect Public Evacuation or Protection in Place? Evacuation or Protection in Place?

19. Summary The single most important piece of knowledge that ANY First Responder can possess is an understanding of what/where they are responding to. This will allow him/her to act in the safest most prudent manner possible to ensure the safety of his/her crew and the public. The Hazardous Materials Team is always available for consultation and should be used accordingly whenever a crew has questions or concerns, The #1 priority is Everyone Goes Home! The single most important piece of knowledge that ANY First Responder can possess is an understanding of what/where they are responding to. This will allow him/her to act in the safest most prudent manner possible to ensure the safety of his/her crew and the public. The Hazardous Materials Team is always available for consultation and should be used accordingly whenever a crew has questions or concerns, The #1 priority is Everyone Goes Home!