1. Condensed Aerosol Fire Suppression and NFPA 2010
The Standard for Fixed Aerosol Fire-Extinguishing Systems
Sponsored by Hochiki America Corporation
V0.06

2. Goals of this presentation:
1) Explain how condensed aerosol fire-extinguishing products operate
2) Provide an overview of the requirements for condensed aerosol fire-extinguishing systems contained in NFPA 2010.
What is condensed aerosol ?
An extinguishing medium consisting of finely divided solid particles, generally less than 10 microns in diameter. Upon the application of heat or electrical energy, the solid aerosol-forming compound is converted into a rapidly expanding gaseous aerosol
Example of solid aerosol-forming compound material
Example of dispersed aerosol system

3. Aerosol generators have various shapes and sizes, based on the quantity of aerosol-forming compound they contain.
This generator contains 20 grams of solid aerosol-forming compound
This generator contains 5,700 grams.
There are many sizes to fit all applications.

4. How big is “generally less than 10 microns in diameter”?
100 µm* – average diameter of a strand of human hair
50 µm – typical length of a human liver cell
15 µm – width of a silk fiber
10 µm – mean longest dimension of a human red blood cell
Condensed aerosol is somewhere in here…
3 - 4 µm – size of typical yeast cell
* A micron is the same as a micrometer (one-millionth of a meter)
Information taken from

5. The solid aerosol particles are inorganic potassium salts.
Particles larger than 10 µm tend to settle to form residue; particles smaller than 10 µm tend to remain suspended in the air.
The solid aerosol particles are inorganic potassium salts.
The gaseous portion includes nitrogen and humidity, with a very small percentage of carbon dioxide and other gases.
Condensed aerosol systems are Total Flooding Extinguishing Systems.
Total Flooding Extinguishing System. A system arranged to discharge an extinguishant into an enclosure to achieve a uniform distribution of that extinguishant, at or above the design application density, throughout the entire volume.

6. How does it work?
Four elements must be present for fire to occur:
A chemical chain reaction
An oxidizing agent (usually oxygen)
Heat (to raise the fuel to its ignition temperature)
Fuel
A fire can be extinguished by removing one of these four elements.
The chemical chain reaction is also called combustion.
Combustion: a chemical reaction that occurs when oxygen combines with other substances to produce heat and usually light (Merriam-Webster)

7. For fire to occur, a fuel must be heated to the point where its surface molecules begin to decompose into simpler gaseous products (pyrolysis).
The pyrolysis process generates some molecules that are very reactive; these are known as free radicals.
The free radicals encounter oxygen in the air. The unstable radicals combine with the oxygen to produce new products.

8. This breaking and forming of chemical bonds between the oxygen in the air and free radicals from the pyrolysis results in more heat.
The heat from the chemical reactions causes more of the fuel to decompose into flammable gaseous products, releasing more free radicals, feeding the reaction with oxygen which creates more heat… The result is a chain reaction that will continue until at least one component is removed.
In fact, flame is a visible sign that the chemical chain reaction is taking place!

9. The chain reaction could be illustrated like this:
{Fuel + Heat = Flammable Gases and Free Radicals} + Oxygen = Chemical Chain Reactions
(Pyrolysis)
GREATER Chemical
Chain Reactions
MORE Heat
(& Flames)
MORE Pyrolysis
of the Fuel
MORE Free Radicals
+ MORE Oxygen
If we can break the reaction we can stop the fire!

10. Upon activation, the generator discharges the aerosol.
The aerosol contains potassium compounds (K)
The potassium binds with the unstable free radicals from the pyrolysis of the fuel. This forms potassium hydroxide (KOH), a stable compound.
{Fuel + Heat = Flammable Gases and Free Radicals} + Oxygen = Chemical Chain Reactions
GREATER Chemical
Chain Reactions
MORE Heat
(& Flames)
MORE Pyrolysis
of the Fuel
MORE Free Radicals
+ MORE Oxygen
With the free radicals gone, the reaction cycle is broken and the fire is extinguished.

11. Upon activation, the generator discharges the aerosol.
The aerosol contains potassium compounds (K)
The potassium binds with the unstable free radicals from the pyrolysis of the fuel. This forms potassium hydroxide (KOH), a stable compound.
{Fuel + Heat = Flammable Gases and Free Radicals} + Oxygen = Chemical Chain Reactions
GREATER Chemical
Chain Reactions
MORE Heat
(& Flames)
+ MORE Oxygen
With the free radicals gone, the reaction cycle is broken and the fire is extinguished.
MORE Free Radicals
MORE Pyrolysis
of the Fuel

12. Condensed aerosol fire-extinguishing systems are fast and effective.
When working with condensed aerosol systems, NFPA 2010 applies. NFPA 2010 is the Standard for Fixed Aerosol Fire-Extinguishing Systems.
This standard contains the requirements for the design, installation, operation, testing, and maintenance of condensed and dispersed aerosol fire-extinguishing systems for total flooding applications.
1.2 Purpose. This standard is prepared for the use by and guidance of those charged with purchasing, designing, installing, testing, inspecting, approving, listing, operating, and maintaining fixed aerosol fire-extinguishing systems, so that such equipment will function as intended throughout its life.

13. Table of Contents (2010 edition)
Chapter 1 – Administration
Chapter 2 – Referenced Publications
Chapter 3 – Definitions
Chapter 4 – General
Chapter 5 – Safety Requirements
Chapter 6 – Components
Chapter 7 – System Design and Installation
Chapter 8 – Approval of Installations
Chapter 9 – Inspection, Testing, and Maintenance
Chapter 10 – Marine Systems
Annex A – Explanatory Material
Annex B – Toxicity Information
Annex C – Reduced Visibility Information
Annex D – Informational References

14. Condensed aerosol fire-extinguishing systems may be used on Class A, Class B, and Class C fuels.
Class A Fire - Fires in ordinary combustible materials, such as wood, cloth, paper, rubber, and many plastics.
Class B Fire - Fires in flammable liquids, combustible liquids, petroleum greases, tars, oils, oil-based paints, solvents, lacquers, alcohols, and flammable gases.
Class C Fire - Fires that involve energized electrical equipment.
4.2.2 Aerosol fire-extinguishing agents shall not be used on fires involving the following materials unless the agents have been tested to the satisfaction of the authority having jurisdiction:
Deep-seated fires in Class A materials
Certain chemicals or mixtures of chemicals, such as cellulose nitrate and gunpowder, that are capable of rapid oxidation in the absence of air
Reactive metals such as lithium, sodium, potassium, magnesium, titanium, zirconium, uranium, and plutonium
Metal hydrides
Chemicals capable of undergoing autothermal decomposition, such as certain organic peroxides and hydrazine

15. 3. 3. 9. 2 Extinguishing Application Density (g/m3)
Extinguishing Application Density (g/m3). Minimum mass of a specific aerosol-forming compound per cubic meter of enclosure volume required to extinguish fire involving particular fuel under defined experimental conditions
excluding any safety factor.
The Extinguishing Application Density will be published by the product manufacturer.
Design Application Density (g/m3). Extinguishing application density, including a safety factor, required for system design purposes.
The safety factor for Class B and Class A fuels must be a minimum of 30%.
You will use the EAD to determine the correct Design Application Density for your condensed aerosol fire-extinguishing projects.

16. Let’s move on to designing a condensed aerosol fire-extinguishing system…
But first…… any questions?

17. Let’s examine the following aspects of a condensed aerosol project:
Calculating the Quantity of Aerosol Required for a Project
System Design and Components
Safety Requirements
Approval, Testing, and Maintenance of Installations
First, how does one calculate the amount of aerosol needed for a condensed aerosol fire-extinguishing system?
The answer is found in Chapter 7, System Design and Installation

18. 7.5.1 Quantity Calculation. The mass of aerosol-forming compound required shall be calculated from the following formula:
m = da x fa x V
where:
m = total flooding quantity [g(lb.)]
da = design application density [g/m3 (lb./ft3)]
fa = additional design factors (see 7.5.2)
V = protected volume [m3 (ft3)]
1) You must know the volume of the space you wish to protect (V).
Imagine a room that is 20’ long, 15’ wide, 9.5’ high.
The volume of the space is 2,850 ft3 (80.71m3)

19. 7.5.1 Quantity Calculation. The mass of aerosol-forming compound required shall be calculated from the following formula:
m = da x fa x V
where:
m = total flooding quantity [g(lb.)]
da = design application density [g/m3 (lb./ft3)]
fa = additional design factors (see 7.5.2)
V = protected volume [m3 (ft3)]
V = 2,850 ft3 (80.71m3)
2) What is the design application density for the aerosol product?
The design application density is the extinguishing application density, including a safety factor.
The extinguishing application density will be provided by the aerosol manufacturer.

20. Suppose that the extinguishing application density is 84 g/m3.
We are protecting an area that contains Class A fuels.
The minimum design application density for a Class A surface fire hazard shall be the extinguishing application density…multiplied by a safety factor of 1.3.
84 g/m3 x 1.3 = g/m3. This is our minimum design application density.
m = da x fa x V
V = m3
da = g/m3
What about fa ?

21. fa stands for “additional design factors”.
7.5.2* Additional Design Factors. In addition to the agent quantity determined by the design application density, additional quantities of agent are required through the use of additional design factors to compensate for any special conditions that would affect the extinguishing efficiency.
What might these include?
Annex A indicates that fan coast down and damper closure time should be taken into consideration.
For our example, let’s suppose that no additional design factors are necessary.

22. Here is our formula:
m = da x fa x V
If we fill in the known information we get:
m = x 80.71
m = 8,813.5 grams
This is the minimum quantity of solid aerosol-forming compound required for this product, based on the design application density.
That completes the calculation.

23. System Design and Components
For condensed aerosol systems, there are no considerations needed for nozzle size, orifice configuration, flow calculations, pipe size, fittings, reducers, tees, valves, flow rate, pipe supports, storage tank location, etc.
…because none of these are needed!
Condensed aerosol fire-extinguishing systems are non-pressurized, self-contained units.

24. NFPA 2001 Clean Agent System NFPA 2010 Condensed Aerosol System
System Flow Calculations
required
n/a
Tee Design Factor
Enclosure Integrity Test
not required
Piping Thickness Calculation
Cup burner method to determine extinguishing concentration for Class B fuels
Safety Factor
20% (class A)
30% (class B)
35% (class C)
30% minimum
Design Factor for Enclosure Pressure
Flow (“Puff”) Testing
NFPA 2010 condensed aerosol systems are different than NFPA 2001 clean agent systems.

25. Working plans and calculations shall be submitted for approval to the authority having jurisdiction before system installation or remodeling begins.
lists the items that shall be indicated on the plans. These include:
Aerosol agent being used
Design application density
For condensed aerosol systems, a description of the generator used, including nominal capacity expressed in units of agent mass
Complete step-by-step description of the system sequence of operations
Complete calculations to determine enclosure volume, quantity of agent…
For condensed aerosol systems, the minimum clearances to combustible materials and the means of egress
Plans and calculations shall be approved prior to installation.

26. Aerosol generators and accessories shall be located and arranged so that inspection, testing, and other maintenance activities are facilitated and interruption of protection is held to a minimum.
Aerosol generators shall be located within or as close as possible to the hazard or hazards they protect.
Aerosol generators shall not be located where they can be rendered inoperable or unreliable due to mechanical damage or exposure to chemicals or harsh weather conditions unless enclosures or protective measures are employed.
Aerosol generators shall be securely installed according to the manufacturer's listed installation manual.

27. Detection, actuation, alarm, and control systems shall be installed, tested, and maintained in accordance with NFPA 70 and NFPA 72.
Initiating and releasing circuits shall be installed in raceways.
Unless shielded and grounded, alternating current (ac) and direct current (dc) wiring shall not be combined in a common conduit or raceway.
For aerosol extinguishing systems, a predischarge alarm and time delay, sufficient to allow personnel evacuation prior to discharge, shall be provided.

28. To avoid unwanted discharge of an aerosol system during maintenance, a supervised disconnect switch shall be provided.
To prevent loss of agent through openings to adjacent hazards or work areas, openings shall be permanently sealed or equipped with automatic closures.
7.3.4 Forced-air ventilating systems shall be shut down or closed automatically where their continued operation would adversely affect the performance of the fire-extinguishing system or result in propagation of the fire.

29. 7. 6. Duration of Protection
7.6* Duration of Protection. The agent design application density shall be maintained for the specified period of time to prevent re-ignition of the fire before effective emergency action can be taken by trained personnel.
4.2.6 Where a total flooding system is used, a fixed enclosure shall be provided about the hazard that allows a specified agent design application density to be achieved and maintained for a specified period of time.
8.1.8* All systems shall have the enclosure examined and tested to locate and then seal any air leaks (other than those included in the approved plans) that could result in a failure of the enclosure to hold the specified agent design application density for the specified holding period.
How should these requirements be understood when working with condensed aerosol fire-extinguishing systems?
What is the “specified period of time”?

30. The UL* hold time is 600 seconds – 10 minutes.
Hold Time. Period of time during which an extinguishant is required to maintain an even distribution throughout the protected volume in an amount at least at the extinguishing application density.
The UL* hold time is 600 seconds – 10 minutes.
How can one determine that the hold time – the “Duration of Protection” – will be satisfied?
Note the comment in Annex A on section 7.6:
A.7.6 Because measuring the concentration of the actual aerosol presents certain difficulties, other physical properties proportional to the aerosol, such as optical transmittance, can be measured, provided adequate calibration between such properties and aerosol concentration can be effected. The measuring technique, procedure, and calibration method shall be endorsed by an appropriate authority.
Other international standards also require a hold time of 10 minutes; for example, ISO 15779:2011

31. Condensed aerosol fire-extinguishing systems are not pressurized systems.
We do not need to maintain a pressurized gas in the enclosure!
The condensed aerosol particles tend to stay suspended in the air, due to their small size (< 10 µm)
UL testing of condensed aerosol systems is performed using the Extinguishing Application Density in an enclosure that is not completely sealed.
In actual installations, the Design Application Density is used, which is 30% more aerosol-forming compound (minimum) than what was used during UL testing.
What does all of this mean?

32. The AHJ is responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure.
Therefore, the AHJ can require whatever they deem reasonably necessary to provide an effective fire suppression system, including a door fan test for condensed aerosol systems.
This test will identify the total leakage in the room. However…
Condensed aerosol fire-extinguishing systems are not pressurized systems.
The testing performed for pressurized systems does not correlate to non-pressurized condensed aerosol systems
For typical hazard enclosures with small amounts of leakage, the additional 30% safety factor included in the Design Application Density will provide more than enough aerosol to satisfy hold time requirements.

33. A condensed aerosol fire extinguishing system may include:
Condensed Aerosol Generators
Notification Appliances, Abort Switch, Manual Release, Disconnect Switch
Listed Releasing Control Panel
Initiating Devices

34. There are many applications for condensed aerosol fire-extinguishing systems.

35. There are many applications for condensed aerosol fire-extinguishing systems.

36. Control Rooms
Electrical Cabinets
Data Centers
Transformer Rooms
Warehouses
Computers
UPS Equipment
Sub-Floor / Above-Ceiling
Mobile Generator Trailers
Telecom Sites / Cell Towers
Archives
Stockrooms
Machinery
Switchgear Rooms
PFC Units
Substations
More…

37. Before we start the next section…
…Any Questions?

38. Safety Requirements
5.1.1 * Any agent that is to be recognized by this standard or proposed for inclusion in this standard shall first be evaluated in a manner equivalent to the process used by the U.S. Environmental Protection Agency's (EPA) SNAP Program.
(from EPA.gov) “The Significant New Alternatives Policy (SNAP) Program is EPA's program to evaluate and regulate substitutes for the ozone-depleting chemicals that are being phased out under the stratospheric ozone protection provisions of the Clean Air Act (CAA).”
Condensed aerosol fire-extinguishing systems are acceptable substitutes for Halon 1301 as a Total Flooding Agent.

39. To prevent human exposure to the aerosol agents by providing a warning of a pending discharge and a delay in the discharge to allow personnel to exit the protected space, a predischarge alarm and time delay shall be provided…
Condensed aerosol generators shall not be employed at less than the minimum safe distance from personnel and combustible materials as specified in the listing of the product.
There are two minimum safe distances to be aware of:
The minimum safe distance to personnel
The minimum safe distance to combustible materials
This information is available from the condensed aerosol manufacturer.

40. 5.2.7.1 Personnel shall not enter a protected space during or after agent discharge.
4.1.1 The fire extinguishing agents addressed in this standard shall be electrically non conductive.
4.1.2 The design, installation, service, and maintenance of aerosol systems shall be performed by persons skilled in aerosol fire-extinguishing system technology.

41. Approval, Testing, and Maintenance
8.1.1 The completed system shall be reviewed and tested by qualified personnel to meet the approval of the authority having jurisdiction.
8.1.2 Only listed equipment and devices shall be used in the systems.
8.1.3 Where field conditions necessitate any change from approved plans, the change shall be approved prior to implementation.
Functional testing requirements are found primarily in Section

42. Reliable primary and 24-hour minimum standby sources of energy shall be used to provide for operation of the detection, signaling, control, and actuation requirements of the system.
8.2.1 Aerosol generators shall be securely fastened to limit vertical or lateral movement during discharge to the manufacturer's specifications.
8.2.4 All condensed aerosol generator mounting brackets shall be fastened securely in accordance with the manufacturer's requirements.
8.2.5 Aerosol generators and mounting brackets shall be installed in such a manner that they will not cause injury to personnel.

43. 9.1.1 Testing, impairment, and restoration of dispersed aerosol systems shall be reported promptly to the authority having jurisdiction.
* Any interfaced system installed in accordance with other installation standards shall be maintained as required by those other standards.
At least every 30 days, an inspection shall be conducted to assess the aerosol system's operational condition.
9.2.2 Inspection
Where external visual inspection indicates that the generator has been damaged, it shall be replaced.

44. At least every 12 months, the enclosure protected by the aerosol system shall be thoroughly inspected to determine if penetrations or other changes have occurred that could adversely affect agent leakage or change volume of hazard or both.
At least annually, all systems shall be thoroughly inspected for proper operation by qualified personnel.
Systems shall be maintained in full operating condition at all times.
Maintenance
Manual
All systems shall be subjected to the manufacturer's maintenance procedures by qualified personnel.

45. A completed copy of the inspection, testing, and maintenance reports performed on these systems in accordance with this standard shall be furnished to the
owner of the system or an authorized representative, and the records shall
be retained for the life of the system.
Condensed aerosol systems may also be used for Marine Systems.
Chapter 10 outlines the deletions, modifications, and additions that shall be required for marine applications.

46. Let’s consider the basic design steps for a system, an equipment room.
The room is 21’-3” x 13’-0” x 9’-0”.
How much aerosol-forming compound will be needed?
NFPA 2010 uses metric units as the requirement.
21’-3” x 13’-0” x 9’-0” becomes
6.48m x 3.96m x 2.74m.
Total volume = m3

47. The aerosol manufacturer will provide the required application density for the product. Let’s suppose this product has a Design Application Density of 100 grams/m3
m = da x fa x V
m = 100 g/m3 x fa x m3
m = 7,031 grams
Next step: determine how many aerosol generators are needed
Remember to allow for the minimum distances (4.2.4)
Locate the aerosol generators as close as possible to the hazards they protect ( )

48. We did not cover every detail of NFPA 2010 in this presentation.
But hopefully, this overview has served as a useful introduction to the standard.
Let’s review a few of the main points that we covered today:
How is the required amount of aerosol-forming compound determined?
7.5.1 The mass of aerosol-forming compound required shall be calculated from the following formula:
m = da x fa x V

49. True or False: Condensed aerosol fire-extinguishing systems are pressurized systems.
Condensed aerosol systems are non-pressurized, self-contained units.
How do condensed aerosol systems extinguish fire?
By breaking the chemical chain reaction of the fire.

50. True or False: Condensed Aerosol Fire-Extinguishing systems are subject to the same requirements as Clean Agent Fire-Extinguishing systems.
False.
NFPA 2001 is applied to Clean Agent Fire-Extinguishing systems.
Is pressure testing of the enclosure required for condensed aerosol fire-extinguishing systems?
It is always the AHJ’s prerogative to require any test they deem reasonably necessary to provide an effective fire suppression system.
Because condensed aerosol systems are not pressurized and due to the nature of the aerosol itself, there is no formula or method that can be used to connect the results of a door fan test with the amount of aerosol that is needed.
Therefore, for typical enclosures with only a small amount of normal leakage, the 30% extra aerosol included in the Design Application Density will provide enough aerosol to satisfy the hold time requirement.

51. Thank you for attending.
Questions?
Thank you for attending.
Bill Denney
Applications and Product Support
Hochiki America Corporation
View NFPA codes on-line:
The contents and statements made in this presentation are based on the operation of condensed aerosol fire-extinguishing products and a published standard, NFPA Every effort has been made to present factual and accurate information; however, NFPA is the final authority on the interpretation of all NFPA codes and standards.
All NFPA 2010 quotations are copyright © the National Fire Protection Association®, 2009