Fire Suppression Techniques Part 2

Common Firefighting Extinguishing Agents Water Foams Halon 1211 CO2 Dry chemicals Dry powders Extinguishing agents are selected based on the materials that are burning. REVIEW CHAPTER 5

Suppressing Class B Fires ( flammable / combustible liquids and gases) Key Terms: Flammable liquid Combustible liquid Compressed gas Flash point Bleve Vapour pressure Vapour density Specific gravity Soluble / insoluble Miscible / immiscible Boiling point Hydrocarbon Polar solvent

Boiling Liquid Expanding Vapour Explosion BLEVE Boiling Liquid Expanding Vapour Explosion

BLEVE Warning Signs

Suppressing Large Class B Fires Extreme caution. Stop leak. Avoid standing in fuel. (wicking) Foam to extinguish large fire. Large volumes of water to cool tank & reduce vapour pressure. (BLEVE) Fog dissipates vapours.

Using Water to Control Class B Fires Water as a Cooling Agent Protect exposures. Cool burning tanks. Cool vapours in tanks. Cool support beams and other materials that may weaken.

Using Water to Control Class B Fires Water as a Mechanical Tool

Using Water to Control Class B Fires Water as a Mechanical Tool

Using Water to Control Class B Fires Water as a Substitute Medium

Using Water to Control Class B Fires Water as Protective Cover

Bulk Transport Vehicle Fires Same techniques for controlling fires in storage vessels. Traffic risks. Water supply limitations. Additional risks posed by location. Instability of vehicle. Container damage.

Passenger Vehicle Fires Approach from sides. Attack upwind. Protect occupants. ALWAYS WEAR SCBA

Passenger Vehicle Fires Dangers: Gas tank Alternative fuel vehicles Shocks Bumpers Tires Battery Pistons on liftgates Strut suspension

Passenger Vehicle Fires

Passenger Vehicle Fires

Control of Gas Utilities Natural Gas 40% Lighter than air. Non toxic but will displace oxygen. Distinctive odour. Explosive range 5-15% Fire / leak. Notify Enbridge Gas. Liquefied Petroleum Gas Stored as a liquid when under pressure in container. Expansion ratio 270-1. Vapour density 1.5. (heavier) Explosive range 1.5-10% NO ODOUR Fire / leak. BLEVE Evacuate area.

Control of Gas Utilities

Suppressing Class C Fires Hydro vaults, transformers, substations, commercial high voltage installations, etc. Recognize the electrical danger. Notify hydro. Shut off power. Use proper extinguishing agents and methods. Ground gradient / step or touch potential. Maintain safe working distances.

Suppressing Class D Fires Combustible metals & alloys: magnesium, sodium, lithium, potassium. No universal class D extinguishing agent. Class D agents – dry powders. Facilities that use or store these metals are required to maintain adequate amounts of extinguishing agent. Water may cause a reaction / explosion. CLASS D ARE CONSIDERED HAZMAT

Practical Learning Outcomes Interior direct attack. Interior indirect attack. Combination attack. Exterior fire attack. Class B fire attack using water fog (2 teams).