Introduction to Fire

The Fire Triangle

Heat Matches

Sun

Cigarette Butts

Ignition Sources

Fuel Wood

Oil

Paper

Gases

Air, Oxygen, or Oxidizers

All three elements must be present to initiate a fire.

The Fire Tetrahedron

Heat Matches

Sun

Cigarette Butts

Ignition Sources

Fuel Wood

Oil

Paper

Gases

Air, Oxygen, or Oxidizers

Once a fire has started it can only be suppressed when one of the three elements is removed, thus stopping the chemical chain reaction.

Chemical Chain

Reaction

The Fire Tetrahedron

Heat Matches

Sun

Cigarette Butts

Ignition Sources

Fuel Wood

Oil

Paper

Gases

Air, Oxygen, or Oxidizers

Water:

Eliminates Heat

CO2: Dry Chemical:

Eliminates Oxygen

Gas Shutoffs:

Eliminates Fuel

Chemical Chain

Reaction

Fire Myths and Fire Truths: Visibility

Myth

Visibility is clear.

Truth

Fires are dark.

Kurt Russell in BackdraftOther great Kurt Russell movies include Silkwood,

Tango & Cash, Tequila Sunrise, and Miracle.

Note that the firefighter in the doorway cannot be seen.

Fire Myths and Fire Truths: Time

Myth

There is ample time.

Truth

There is little or no time.

Fire Myths and Fire Truths: Death

Myth

People burn to death.

Truth

People die from smoke inhalation. Carbon Monoxide.

This is why smoke detectors are of greater

value than heat detectors in most instances.

Classifications of Fire

Class A

Ordinary Combustibles• Paper• Wood• Plastics

Class A fires will generally leave an ash.

Class B

Flammable Liquids and Flammable Gases• Gasoline• Oil• Acetone

Class C

Class A or B Fires with an Electrical Hazard• Energized Electrical Equipment• Outlets

Class D

Combustible Metals• Potassium• Magnesium• Sodium

Class K (Kitchen)

Cooking Oil and Fat

Types of Fire Extinguishers

Class A

Water• Eliminates Heat

Class AB

Foam• Eliminates Oxygen

Class BC

CO2, Dry Chemical, or Halon• Eliminates Oxygen

Class ABC

Dry Chemical• Eliminates Oxygen

Class D

Dry Powder• Eliminates Oxygen

Class K (Kitchen)

Wet Chemical• Eliminates Oxygen

Note: Many Class K extinguishers are also suitable for Class A fires.

Class AC

Water Mist• Eliminates Heat & Protects Equipment

Using an Extinguisher

When To Use?

• When it is absolutely necessary.

• When the is a fire between you and your escape route.

• When the fire is relatively contained; e.g., a garbage can.

• When there is a realistic opportunity to put out the fire.

YES NO

Positioning

• Between the fire and an exit or escape route.

• Back three to four feet from the front of the fire.

• Always back away from the fire, keeping an eye out for flare-ups.

P.A.S.S.

• Pull the Pin

• Aim (base & front of fire)

• Squeeze (the handle)

• Sweep (moving front to back)

Fire Alarm Systems

Alarm Activation

1. Pull Station

2. Heat Detector

3. Smoke Detector

4. Sprinkler

5. Electrician

6. Malfunction

Fire Suppression Systems

Hoses & Standpipes

• Hoses are a LAST resort.• Standpipes are for fire

department use only. Do not uncap them.

Sprinklers

• Individual sprinklers will activate when heated to the appropriate temperature.

• Release about 75 to 150 liters/minute.

INERGEN®; Halon; CO2 Systems

• Deprive fires of oxygen.

• Dangerous for humans in such areas.

• LSC, Chemical Stores Facility, Tupper.

Fire Evacuation Procedures

Upon Hearing an Alarm

• Exit the room.• Close the door behind you (leave unlocked).• Follow the wardens instructions.• Follow set evacuation routes.• Exit the building.• Keep back from the building (min 50m).• Wait for instructions from wardens, Dal

Security, or the HRM Fire Service.

If YOU Discover Fire

• Try and put out if it meets previous criteria.

• Close the door to the room and activate a pull station.

• Exit the building.

• Give all information to wardens, Dal Security, or HRM Fire Service.

Persons with Disabilities

• If you have a disability that prevents you from leaving a building via stairwells, set up a buddy-system.

• Stay in designated “shelter-in-place” areas.

Re-Entering a Building

• DO NOT re-enter a building until given the “OK” by the wardens, Dal Security, or the HRM Fire Service.

The Law

• You MUST leave a building upon hearing an alarm, even in the case of a fire alarm drill.

• The Fire Service has the authority to fine people who do not evacuate buildings.

Final Thoughts

Fires are Dangerous

• Treat fire and fire safety with respect.

• There are rarely second chances.

• Open flames are not permitted at Dalhousie unless cleared through the Safety Office.

Fires are Rare on Campus

• Dalhousie has had fires in the past, but over the past decade they have been small, with minimal damage and no serious injuries or deaths.

• Small houses and buildings, prevalent at Dalhousie, present the highest risk of fire.