Fire Protection Fundamentals Notes

1. FIRE PROTECTION FUNDAMENTALS

1.1 UNDERSTANDING OF FIRE SCIENCE

Fire science relates to the behavior of fire, from ignition, growth and spread, to the impact of fire on structures and human lives.
It also covers:
- Fire control strategies
- Fire retardants
- Fire detection technologies
- Fire suppression technologies
- Fire containment
- Human behavior and evacuation

Fire Science Research Program Focuses

Survival of fire
Reduce loss of properties
Minimize the effect of fire
Developing better fire risk mitigation strategies
Developing better fire-resistant and fire-retardant materials

General Design Criteria

Fire Barriers
Flame Spread
Roofing Systems
Penetrations
Carpets and Rugs

Approved / Listed Equipment

UNDERWRITERS LABORATORY (UL)
FACTORY MUTUAL (FM)
Tested and comply with the Testing Organizations.
Acceptable by the authority having jurisdiction:
- Fire Brigade / Insurance Company / Owner
The use of listed equipment is important for demonstrating that fire protection system components can function in accordance with the requirements.

Example Approved Equipment

Various Evapco cooling towers and components along with their specifications and certifications as approved by Factory Mutual (FM).

5. LIFE SAFETY

Addresses construction, protection, and occupancy features.
NFPA 101, The Life Safety Code focused on life safety issues
- Buildings
  - Industrial building: General, Special, High Hazard, and Open Structure.
  - To define the occupancy hazard: Low/ordinary/high depending on the amount and type of fuel to burn
  - Refer to NFPA 101 to design exit access, travel distance, number of exits, exit width, emergency lighting, etc.
- Exit and Arrangements
  - Emergency evacuation route.
  - Path free of tripping hazards and enough illuminations.
  - At least two means of egress are required at every level, story, or section of the process structure.
  - Proper ladders design
- Enclosed Process Structures
  - Unprotected Vertical Opening (e.g., Graded floor)
  - Every floor must have direct access to enclosed stairs.
  - Enclosed stairs to provide PPE from smoke and fire during emergency egress.
  - Enclosed stairs to be fire resistance:
    - 1-hour rating < 3 stories
    - 2-hours rating > 4 stories

Fire Control

Types of Fire

There are innumerable situations where gases, liquids, and hazardous chemicals are produced, stored, or used in a process that, if released, could potentially result in fire. Hydrocarbon fires are a principal concern.
The mode of burning depends on the characteristics of the material released, temperature, pressure, etc.
- Jet Fires
- Flash Fire
- Pool Fires (2D Fire)
- Running Liquid Fire (3D Fire)
- Boiling Liquid Expanding Vapor Explosions (BLEVE) / Fire Ball

General Control Methods

Extinguishment of Fire
- Reducing the heat release rate by cooling medium into the fire plume.
- Separating fuel vapors from oxygen.
- Inhibiting chemical chain reaction.
- Extinguishment of fire by cooling, smothering from produced steam, or dilution of some liquids.
- Distribution of extinguishing agent to absorb heat released.
Control of Burning
- Controlling fuel burning, flow of fuel, and fuel leaking.
- Example: Fire involving flowing gaseous fuel will not stop until the source of fuel is stopped.
Exposure Protection
- Provide protection by the application of water to structures.
- Limits the surface temperature of exposed structures to a level that will minimize damage and prevent failure.
Prevention of Fire
- Fire protection systems achieve prevention of fire by operating until flammable vapor, gases, or hazardous materials dissolve, dilute, or cool.

Fire Fighting Agent

Water
- Not suitable for electrical (Class C) fires.
- Effective cooling agent by fog or spray.
- $3.8$ liters of water absorb about $1512$ k/cal when vaporized to steam.
Foam
- Air-filled bubbles that float (blanket) on the surface of a flammable liquid that extinguish fire by excluding air and cooling the fuel.
- Low expansion foam to extinguish 2D (pool) flammable liquid fire.
- High expansion foam to extinguish 3D fire.
- Types: Fluoroprotein and Aqueous Film Forming Foam.
Carbon Dioxide
- Noncorrosive and electrically nonconductive.
- $CO_2$ is stored in liquid form for pressure systems and gaseous in high-pressure systems.
- Need time-delay pre-evacuation since potential to affect the nervous systems and fatality.
- Verification of $O_2$ level required prior reentry.
Dry Chemical
- Three types of dry chemical: Sodium bicarbonate, Potassium Bicarbonate, and Monoammonium Phosphate.
Clean Agents
- Nonconductive, volatile, do not leave a residue upon evaporation.
- Two categories: halocarbons and inert gas.
- Applications: Electrical and electronic hazards, Concealed spaces, Telecommunications equipment.

Passive Protection Systems

A system that focuses on non-moving structural parts to constrain fires or slow the spread.

1. Spacing and Layout

To minimize personnel injuries and overall property damage.
- Example: Keeping fuel separate from a potential source of ignition or tank-to-tank spacing.
Fire brigade access to be provided from at least two directions.
“Guidelines for Facility Sitting and Layout” – CCPS, 2003: Complete discussion of layout.
Fire barriers to be consider when recommended spacing cannot be met.
- Separating Office Building from adjacent area.
- Large Turbine from Compressor.
- Warehouse from adjacent area.

1. Spacing and Layout - Emergency Access

Illustrative diagram showing emergency access routes and facility layout.

2. Fire Proofing

Part of passive fire protection.
Fire Proofing is a fire-resistant material or system that is applied to a surface to delay heat transfer.
API 2218, Fireproofing Practices in Petroleum and Petrochemical Processing Plant: Reference
Fire resistance rating selection:
- Fire scenario
- Hazard Evaluation and inventories of potential fuels.
- Response time – ERT / Fire Brigade.
Testing Fireproofing materials: UL1709 and ASTM E 1529 – Represent flammable liquid and pool fire conditions.
Type of Fireproofing materials:
- Dense Concretes
- Lightweight Concretes
- Subliming and Ablative Mastics.
- Intumescent Epoxy Coatings

2. Fire Proofing

3. Containment and Drainage

Retain/hold spills released from process systems.
Containment design with a solid floor with curb, dikes, or wall and not collected under process equipment. (Runaway Avoid pool fire to source)
Trench design, collect and control spills within only one containment. Prevent becoming a source of fire spread to another zone.
Trench cover  NFPA 30.

4. Electrical Area Classification

Electrical equipment  Potential source of ignition.
Provide a graded measure of ignition risk within flammable gas concentration/ignition mixture and accumulations of combustible dust.
Guidance at NFPA 70B.
Traditional electrical classification
- Class I – Hazardous atmosphere.
- Class II
- Class III – Accumulations of filters or flying.

5. Static Electricity

Static electric accumulated on materials via friction but when conductors involve charge are quickly dissipate.
When non-conductors involve: Charge accumulated then sudden recombination of positive and negative, then spark occurred.
Eliminating risk by grounding and bonding.

Active Protection Systems

A System where fire protection devices are manually/integrated with a detection system designed to automatically activate upon sensing fire.

1. Water Distribution/Hydrant

Fire Mains
- Hydraulic design  Gridded / Looping Piping Distribution
- Pipe Diameter
- Underground pipe  Buried at least 3 feet to prevent damage.
- Materials  Ductile Iron, Polyethylene, PolyvinyCloride, Carbon Steel
Valve and Fittings
- Post Indicator Valve
- Fire Hydrant – Spaced at a maximum of 200 feet (60m)

2. Fire Water Pumps

Minimum pumping capacity  1,500 gpm (5,700 l/m)
Design in accordance with NFPA 20.
Location: Close to source of water and away from hazardous area.
Fire Hydrant – Spaced at a maximum of 200 feet (60m)

Pumps Type and Rating
- Horizontal Centrifugal Pumps
  - +ve head suction supply.
- Vertical Shaft – Suction lift.
- Jockey Pump – To maintain a predetermined systems pressure (10-15 psi above the main pump start-up)
Fire Water Pump Driven
- Electric motor
- Diesel Engine – Fuel supply > 8 hours operations.
Miscellaneous Equipment
- Relief valve- Connect to the water source
- Pressure gauge – Minimum 3 ½” diameter.
- Panel Controllers
  - Automatic, Remote Manual, and Manual Local starting.

FIRE WATER PUMPS

Example Jockey Pump Specifications: Brand Wilo, Model: MVI 812.

Automatic Sprinkler System

Duty Pump (Electric Fire Pump)
- Brand: ITT-AC Pump
- Model: 8x6x12 F-M 8100 Series Fire Pump
- Controller Cut-in: 140 psi
- Cut-Out: Manual stop

Automatic Sprinkler System – Standby Pump

Standby Pump (Diesel Fire Pump)
- Brand: ITT-AC Pump
- Model: 8x6x18F 8100 Series
- Diesel Tank Capacity: 293 gallons
- Standby Pump Controller Cut-in: 130 psi
- Cut-out: Manual Stop

3. Sprinklers

Wet Pipe Types
- The most common and least complicated.
- All pipes are full of water
- Operating mechanism is based on the fusible bulb deteriorated/failed, then water immediately discharges through sprinkler head
Dry Pipe Types
- For unheated building in cold climates.
- Minimizes corrosion.
- Pipe filled with compressed air  Bulb fused  Compressed air released  Water in and discharge.
Pre-Action Types
- The principal difference with Dry Pipe is the water supply valve operated independently via automated detector, then water entering the overhead piping.
- Heat from fire will fuse the bulb  water discharge.
Deluge Types
- A sprinkler system design with an open sprinkler head.

Design - Layout

The piping configuration for a sprinkler system may be
described as any of the following:

Pipe Schedule
Hydraulically designed
Tree piping layout
Looped piping layout
Gridded piping layout
NFPA 13 Installation of Sprinkler Systems
The advantages of a tree piping configuration include:
- Simplicity of layout
- Hydraulic calculation easy to complete
- Economic design for small systems
- Easily modified
A looped piping configuration provides more efficient water distribution than a tree-piping configuration. The looped distribution main provides two paths for water delivery to the individual branch lines. Splitting the flow in the system reduces the pressure loss in the system.
The advantages of a gridded piping configuration include:
- More economical pipe sizing
- Multiple flow paths allow smaller piping
- Capabilities of the system are known

Sprinklers - Design

Sprinkler head selection is based on the Temperature Rating and color coding

4. Water Spray Systems

Application
- Cooling down metal - Apply water to protected surface.
- Control fire intensity – Spray water on equipment.
- Prevent ignition Protect vital instruments run – Cooling multiple conduits and outside trays.
- Control toxic vapor cloud – create turbulence and mixing of air
Design
- Detection and actuation design
  - Fire Detector
  - Combustible Gas Detector
  - Manual Station
- Explosion Protection – eliminate damage
  - Underground piping
  - Deluge valve located remotely > 50 feet from the area to be protected.
- Water Spray Nozzle – discharge characteristic.
- Positioning of spray system – proper coverage

5. Foam Systems

Primarily for extinguishment of two-dimensional surface fire involving liquid.
Three types of foam:
- Low expansion foam  up to 20 times foam to solution volume
- Medium expansion foam  from 20 to 200 times foam to solution volume
- High expansion foam  from 200 to 1000 times foam to solution volume.
Not suitable for fire involving pressurized gases and Liquefied Petroleum Gases (LPG) and three-dimensional fires.
Application either in:
- Fixed types
- Semi fixed types
- Portable types

Foam Systems

Diagrams of various foam system setups including pressure proportioners, detectors, foam solutions, foam makers, foam pourers, bladder tanks, monitors and generators.

6. Clean Agent

Covered TX, HT, and LV Room, DATA Centre, UPS, and Gen-set Room

7. Carbon Dioxide Systems

Carbon dioxide or $CO_2$ is a colorless, odorless, electrically non-conductive gas that's highly efficient as a fire suppression agent. Carbon Dioxide fire protection systems use intelligent, reliable, and fast-acting control panels to quickly sense a fire before it can cause damage to property.

8. Dry Chemical

Dry Chemical Powder Fire Extinguishing System When introduced directly to a fire, dry chemical powder extinguishes flames almost immediately. Dry chemical powder is intended for use in extinguishing fires involving bulk chemical agents and liquefied gases.
Dry chemical is usually a mix of monoammonium phosphate and ammonium sulfate, the former being the active one. The mix between the two agents is usually 40-60%, 60-40%, or 90-10% depending on local standards worldwide.

9. Water Mist Systems

Water is forced through micro nozzles at very high pressure to create a water mist with the most effective firefighting drop size distribution. The extinguishing effects give optimum protection by cooling, due to heat absorption, and inerting due to the expansion of water by over 1,700 times when it evaporates.

10. Portable Fire Suppression Systems

Portable Fire Suppression Systems

Fire Classification

Class A
- European/Asian: A
- American: A
- Description of Fuel: Ordinary combustible materials.
Class B
- European/Asian: B
- American: B
- Description of Fuel: Flammable and combustible liquids
Class C
- Description of Fuel: Flammable gases
Class D
- European/Asian: D
- American: D
- Description of Fuel: Combustible metals
Class E
- Description of Fuel: Involves live electrical equipment
Class K
- Description of Fuel: Cooking oil and fat

Placement/Accessibility of Extinguisher

Class A
- Maximum Travel Distance to Fire Extinguisher: 75 feet
- Maximum area that one extinguisher can protect and meet the 75 ft. rule = 11,250 sq. ft.
Class B
- Maximum Travel Distance to Fire Extinguisher: 50 feet
- Maximum area that one extinguisher can protect and meet the 50 ft. rule = 5,000 sq. ft.
Class C
- In accordance with the Class A or B hazard it is protecting.
Class D
Class K
- Maximum Travel Distance to Fire Extinguisher: 30 feet
- Maximum area that one extinguisher can protect and meet the 30 ft rule = 1,800 sq. ft.