FM-200 (HFC-227ea)
Gas Suppression System Design

FM-200 (HFC-227ea) system design is not without its challenges; the key among these are the location of the containers. As with other synthetic gases, the storage of cylinders (containers) generally needs to be close to the suppression area. However, the distinct advantage of FM-200 is that it requires less storage space. Stored as a liquid, FM-220 is denser than liquid inert gasses and the like.

Specific FM-200 System Design Criteria

It is not permitted for changes to equipment, pipework, or nozzle positions to be made without the authority of the suppression system’s design engineer.

FM-200 System Design Concentrations

Proper and safe FM-200 system design requires that agent design concentration falls within a design window limiting the concentrations. FM-200 is accepted for use in occupied spaces when the design concentration falls within the 7.9% to 8.5% window.

However, as a fire burns, it consumes oxygen and results in harmful gases and particulates such as carbon monoxide increasing in the atmosphere within the protected space. These additional gases may result in oxygen levels below the design threshold. For these reasons, the designer requires a lot of information concerning room usage after completing the suppression system.

New FM-200 systems are rare in Australia, and finding design engineers who have the level of experience required is getting harder. Fire Systems Products’ team has years of experience designing and engineering systems to meet our clients requirements whilst remaining standards-compliant.

The FM-200 System Design Scope

FM-200 design includes assessing the agent storage location and quantity required, pipework layout and length, flow restrictions through pipework and accessories, and fixing the location and quantities of discharge nozzles for uniform distribution of the agent throughout the space.

For a Total Flooding System, many factors determine the quantity of the agent required, including the design standard used. Additionally, the type of fire to be extinguished, the size and shape of the space, the Hold Time required by the standard and any leakages determined by the design and Door Fan Testing. Consider some additional agent if the plans submitted to the designer do not match the final structure delivered to the client.

Often, engineers, building designers or owners can provide plans with piping sizing and routing and the nozzle locations and quantity of agent containers already located within the space. This is problematic, as the plans require checking by an authorised fire systems design engineer before work commences on these systems, as many critical factors can be overlooked. And so, the effectiveness may not have been incorporated into these designs. Once a final design is established, it is not permitted for changes to equipment, pipework, or nozzle positions to be made without the Design Engineer’s written authority.

To take care of the system pressure drop and establish the required pressure at the nozzles, the system design engineer utilises software calculations to ascertain the quantity of agent in each cylinder and the number of cylinders based on the fill density standard container size.

Our Team

With 60+ years combined fire industry experience, our team provide proven gas suppression designs, and focused value-added engineering solutions. Furthermore, Fire Systems products has fostered strong relationships with leading manufacturers and industry partners, meaning that our system designers regularly receive the latest product information and training to enhance their level of expertise and the quality of our work.

In addition, the design team at Fire Systems Products can provide you with a site-specific FM-200 design solution that supports the mitigation of safety risks. This process involves a consultation with our experts to evaluate the project’s requirements.

Furthermore, we have specified, designed, and commissioned high-quality FM-200 gas fire suppression system protection for many major institutions and commercial operations throughout Australia through our industry partners, complying with our duties as a designer under the Regulations.

60+ years of experience in the fire industry

Information Required for FM-200 System designs:

• Room Dimensions (Room Volume)
• Set of plans (to scale)
  • Fire Panel Type and location
  • Gas Suppression Cylinders location
  • Pressure relief damper location
  • Access requirements (steps, hoist, etc.)
• Underfloor protection required?
• Ceiling void protection?
• Site location
• Site photos
• Ceiling type
• Wall type
• Assets protected
  • Computer Rooms
  • Subfloors
  • Data Centres
  • Telecommunications
  • Museums
  • Libraries
  • Archives
  • Machinery Spaces
  • Switchgear
  • etc

Limitations of FM-200 System designs

When Designing any Fire Suppression system, it is essential to understand its limitations. FM-200 Gaseous fire suppression system designs cannot protect:

1. Chemicals containing a supply of oxygen, such as, cellulose nitrate, used in gunpowder, nail polish and lacquer finishes.
2. Mixtures containing oxidising chemicals, such as, sodium nitrate, used in fertilisers and explosives.
3. Chemicals can undergo auto-thermal decomposition, where a chemical begins to decompose if it reaches a specific temperature.
4. Reactive metals, e.g. the elements sodium, potassium or magnesium.
5. Areas where large surfaces, heated (not by fire) to a temperature that breaks down the chemical structure of the extinguishing agent. because of this, the agent is then unable to extinguish a fire.

Alternate Chemical Names

• Propane, 1,1,1,2,2,3,3-heptafluoro-
• 1,1,1,2,2,3,3-Heptafluoropropane
• Heptafluoropropane
• 1-Hydroheptafluoropropane
• R 227ca
• 1,1,2,2,3,3,3-Heptafluoropropane
• HFC 227ca
• 1H-Heptafluoropropane

References

• CAS Common Chemistry

Trademarks

FM-200 is a registered trademark of Dupont.

For more information about FM-200 Gas Suppression System design.