Title: TM%20650%20-%20Safety%20Management%20Fire%20Hazards%20
1TM 650 - Safety ManagementFire Hazards Life
Safety
- Carter J. Kerk, PhD, PE, CSP, CPE
- Industrial Engineering Department
- South Dakota School of Mines
2Assignment
- Read Chapters 11 13
- HW12
- Chapter 11, pages 245-6
- Problems 1-19, divisible by 3
- Chapter 13, pages 284-5
- Problems 1-42, divisible by 3
3Fire Elements
- Three elements are required to start and sustain
fire oxygen, fuel, and heat. - Sometimes a 4th element, chemical reaction, is
added - Since oxygen is generally present, fire hazards
usually involve mishandling of fuel or heat
4The Fire Triangle
Heat
Fuel
FIRE
Oxygen
5Elements Of FireFire is a chemical reaction
involving rapid oxidation or burning of a fuel.
It needs four elements to occur Fuel
Oxygen Heat Chemical reaction.
- Take away any one of these factors, and the fire
cannot exist!
October Is National Fire Prevention Month
6Fire Problem in US Annually
- 1 million fires involving structures
- 8000 deaths
- gt20,000,000,000 total property loss
- These figures do not include indirect costs
- Litigation, investigation, etc.
7Leading Causes of Industrial Fires
- Electrical (23)
- Smoking materials (18)
- Friction (10)
- Overheated materials (8)
- Hot surfaces (7)
- Burner flames (7)
- Others (27) Sparks, Spontaneous ignition,
Cutting, Welding, Arson, Chemical action,
Lightning, Molten substances
8Fire Related Deaths
- 25 of fire-related deaths are from burns
- 2/3rds are from inhalation of CO, smoke, toxic
gases, asphyxiation - 10 are from mechanical injuries, relating to
falls or falling materials - Overall death rate is 2.8 per 100,000 population
- lt5 yrs old higher than average
- 75-85 ages 12.5 gt85 years 22.2
- Deaths are often alcohol related (perhaps gt80)
- Most fatal fires involve 1 or 2 victims
- Large losses receive most publicity
9Infamous Fireshttp//www.olafire.com/OtherFires.a
sp
- 12/30/1903 602 Chicagos Iroquois Theater
- 3/25/1911 145 - Triangle Shirtwaist Factory, NYC
- 11/28/1942 492 Cocoanut Grove nightclub,
Boston - 7/6/1944 168 Ringling Brothers and Barnum
Bailey Circus, Hartford, CT - 12/1/1958 95 - Our Lady of Angels Grade School,
Chicago - 5/28/1977 165 Beverly Hills Supper Club,
Southgate, KY - 11/21/1980 85 - MGM Grand Hotel, Las Vegas
- 12/4/1980 26 Stouffer Inn, NYC
- 9/3/1991 25 Imperial Foods, Hamlet, NC
- 9/11/2001 2752 - World Trade Center
- 2/20/2003 100 Great White concert at The
Station nightclub, West Warwick, RI
10Fire or Combustion
- Chemical reaction between oxygen and a
combustible fuel - Combustion is the process by which fire converts
fuel and oxygen into energy, usually heat - By-products include light and smoke
11Ignition of Fire
- Spark or open flame
- Sufficiently high temperature
- given a sufficiently high temp, almost every
substance will burn - Ignition temperature or combustion point
- temp at which given fuel can burst into flame
12Explosive Limits
- UEL
- upper explosive limit
- LEL
- lower explosive limit
13Fire is a Chain Reaction
- For combustion to continue, there must be a
constant source of fuel, oxygen, and heat - Exothermic Reactions
- create heat
14Chemical Reaction
- During combustion, carbon atoms are released
which combine with the oxygen present to form - carbon dioxide (CO2)
- with ample oxygen present
- carbon monoxide (CO)
- insufficient oxygen, incomplete combustion
- colorless, odorless deadly gas
15Chemical Rxns Cont.
- Hydrogen atoms released during fire combine with
oxygen present to form water - Synthetic polymers (plastics and vinyls) form
deadly fumes during combustion
16Hot Work
- Operations such as welding, brazing, soldering,
cutting, chipping, grinding, drilling Use of
spark-producing power tools Heat guns - Flammable, combustible, or ignitable materials
should be kept gt 20 feet away or covered with
flame-retardant material
17Extinguishing a Fire
- Removing the fuel source
- Starving it of oxygen
- Cooling below combustion point
- Remember the triangle
18Heat Transfer
- Heat transfers from a fire to surrounding objects
which may ignite, explode, or decompose - Usually simultaneous means of heat transfer
- conduction - direct contact
- radiation - wave transfer of heat to a solid
- convection - movement of hot gases
19Spontaneous Combustion
- Rare, but possible
- Pile of oil-soaked rags
20Sources of Fire Hazards
- Fuel is present almost everywhere
- paint on seemingly non-fuel items
- even fire walls are not fire-proof, they only
slow the fire - Oxygen is almost always present
- What is the passive fire suppression technique?
- Lack of sufficient heat
21Classes of Fire (Table 13.1)
- Class A Fires - Ext. w/ foam, water, dry
chemicals - solid materials wood, plastic, textiles, paper,
housing, clothing - Class B Fires - Ext. w/ dry chemicals, foam, CO2
bromotrifluoromethane - flammable liquids and gases
- Class C Fires - Ext. w/ CO2, dry chemicals,
bromotrifluoromethane - Energized electrical equipment (live electricity)
- Class D Fires - Ext. w/ special powders
(graphite, sand) - Combustible, easily oxidized metals (aluminum,
magnesium, titanium, zirconium, sodium, lithium,
potassium)
22Classes Of FireFires are classified according to
the types of objects being burnedClass A
ordinary combustibles such as wood, paper, cloth,
rubber or certain types of plasticClass B
flammable or combustible gases and liquids such
as gasoline, kerosene, paint, paint thinners or
propaneClass C energized electrical equipment
such as appliances, switches or power
toolsClass D certain combustible metals such
as magnesium, titanium, potassium or sodium.
23Fire ExtinguishersThe faceplate of every fire
extinguisher shows the class or classes of fire
it is designed to fight.To properly use a fire
extinguisher, follow the P-A-S-S procedure
P Pull the pin A Aim the extinguishers hose or
nozzle at the bottom of the fire S Squeeze the
trigger S Sweep it slowly back and forth,
covering the entire fire with the extinguishing
substance.
P
A
S
S
October Is National Fire Prevention Month
24Methods of Controlling Extinguishing Fire
- Remember the fire pyramid
- Cool the fire
- Limit the oxygen supply
- Remove the fuel
- Inhibit the reaction producing hydroxyl (OH)
radicals
25Terminology
- Flash Point
- lowest temp at which vapors are produced in
sufficient concentration to flash in the presence
of an ignition source - Fire Point
- lowest temp at which vapors will continue to
burn, given an ignition source - Auto-Ignition Temperature
- lowest temp at which vapors of a liquid or solid
will self-ignite without a source of ignition
26Flammable Combustible Liquids
- Flammable Liquids
- flash point below 100 degrees F
- Combustible Liquids
- flash point gt 100 degrees F
- See Figure 11.1
27Flammable Liquid Classes
- Class I-A
- Flash point below 73 F, boiling point below 100 F
- Class I-B
- Flash point below 73 F, boiling point gt 100 F
- Class I-C
- 73 F lt FLASH POINT lt 100F
28Combustible Liquid Classes
- Class II
- 100 F lt Flash Point lt 140 F
- Class III-A
- 140 lt Flash Point lt 200 F
- Class III-B
- Flash Point gt 200 F
29NFPA 704
- Diamond labeling system to aid in quick
identification of hazards present when substances
burn - Red - Flammability - Top Quarter
- Blue - Health - Left Quarter
- Yellow - Reactivity - Right Quarter
- White - Special Information) - Bottom Quarter
- Used on product labels, shipping cartons,
buildings
30NFPA Symbol System for Identification of Hazards
of Materials (see NFPA 704)
ReactivitySignal(Yellow)
Flammability Signal(Red)
Health Signal (Blue)
SpecialSymbols(Radiation, Use ofWater is
Hazardous)
31NFPA Symbol Flammability Signal
DegreeofHazard FLAMMABILITYSusceptibility of Materials to Burning
4 Materials which will rapidly or completely vaporize at atmospheric pressure and normal ambient temperature, or which are readily dispersed in air and which will burn readily
3 Liquids and solids that can be ignited under almost all ambient temperature conditions
2 Materials that must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur
1 Materials that must be preheated before ignition can occur
0 Material that will not burn
32NFPA Symbol Reactivity Signal
DegreeofHazard REACTIVITYSusceptibility of Release of Energy
4 Materials which in themselves are readily capable of detonation or of explosive decomposition or reaction at normal temperatures and pressures
3 Materials which in themselves are capable of detonation or explosive reaction but require a strong initiating source or which must be heated under confinement before initiation or which react explosively with water
2 Materials which in themselves are normally unstable and readily undergo violent chemical change but do not detonate. Also materials which may react violently with water or which may form potentially explosive mixtures with water.
1 Materials which in themselves are normally stable, but which can become unstable at elevated temperatures and pressures or which may react with water with some release of energy but not violently
0 Materials which in themselves are normally stable, even under fire exposure conditions, and which are not reactive with water
33NFPA Symbol Special Symbols
ApprovedSymbols SPECIAL HAZARDS
OX This denotes an oxidizer. A chemical which can greatly increase the rate of combustion / fire.
W Unusual reactivity with water. This indicates a potential hazard using water to fight a fire involving this material.
34Fire Detection Systems
- Thermal expansion detectors
- heat sensitive metal link that melts at
predetermined temp - Photoelectric fire sensor
- detects changes in infrared energy radiated by
smoke and smoke particles, obscuring the beam - Ionization or radiation sensors
- uses the tendency of a radioactive substance to
ionize when exposed to smoke - Ultraviolet or infrared detectors
- detects radiation from fire flames
35Fire Extinguishing Systems
- Large facilities may have fire brigades
- Standpipe and hose systems
- Automatic sprinkler systems
- usually water
- pipes can be kept filled or empty
36OSHA Fire Standards
- 29 CFR Subpart L
- Fire Protection
- 1910.155-156
- Portable Fire Suppression Equipment
- 1910.157-158
- Fixed Fire Suppression Equipment
- 1910.159-163
- Other Fire Protection Systems
- 1910.164-165
- 29 CFR Subpart E - Exits, Emergency action
plans, means of egress
37Life Safety Code
- NFPA 101
- protecting vehicles, vessels, and lives of people
in buildings and structures - address construction, protection, and occupancy
features
38Hot Work Program
- Companies that have flammable, combustible, or
ignitable materials and need to perform hot work
in or around these materials need to have a Hot
Work Program - Written Program
- Pre-work inspection
- Signed permit to show inspection and approval
39Fire Safety Objectives
- Getting occupants out safely
- Minimizing property loss for structures and
contents - Minimizing interruption of operations
40Fire Safety Fundamentals
- Site Planning Accessibility
- Separation of Structures
- Building Construction Materials
- Fire Resistance Ratings
- See Brauer Table 16-4
- Confinement / Compartmentation
- Consider Fire Load and Fire Spread
41Industrial Process Fire Hazard
- Venting
- Fire Walls
- Welding Cutting
- Hot Work Permits
- Indoor Storage of Flammable Liquids
- Warehouses
42Life Safety
- Protection of human life is 1 priority
- Understanding human behavior in fires
- General Principles of Life Safety
- 3 classes of hazard low, ordinary, high
- Type of occupancy residential, assembly,
hospitals, industrial
43General Principles of Life Safety
- Interior Finishes
- Means of Egress
- Capacity
- Number of Means of Egress
- Exit Access
- Width
- Stairs
44Assignment
- Read Chapters 11 13
- HW12
- Chapter 11, pages 245-6
- Problems 1-19, divisible by 3
- Chapter 13, pages 284-5
- Problems 1-42, divisible by 3