Clean Agent Suppression System

A Comparative study on Inert Gas (IG) and Synthetic gas FireSuppression Agent

1.      Objective of the Study

To find out a recommendation for clean agent suppression system suitable for total flooding of electrical control panel room.

2.      Ref:

ü  Manufacturers catalog/Quotation

ü  NFPA 2001

3.      History of Fire Suppression System

Sprinkler systems are the most widely used form of fire suppression in the world. Their primary function is to preserve a building’s structural integrity long enough for people to evacuate, and for the fire department to arrive. Sprinklers perform this function very well, which explains why they have been the fundamental means of fire protection for nearly 150 years. Unfortunately, sprinklers do little to preserve the contents of a building, and in fact, often contribute to the destruction of building contents, especially when those contents include sensitive electronics, paper archives or other valuable artifacts.

4.      How Clean Gas/Agent Fire Suppression Introduced

Halon was introduced as an ideal agent for solving this problem in the 1960s. It was non-conductive and it left no residue upon evaporating. But Halon was phased out of use in new extinguishing systems in the early 1990s because of its potential to deplete the ozone layer. Various different agents were introduced in the decades following the halon phase out. These agents are commonly referred to as “clean agents” and include HFC-227ea (also known by the Chemours™ brand of FM-200™), HFC-125 (also known by the Fike Corporation brand of ECARO-25^®), FK-5-1-12 (also manufactured by 3M™ and sold under the brand of Novec™ 1230) and various Inert Gases (IG), which include IG-55 (a 50/50 mix of argon and nitrogen), IG-541 (50/42/8 mix of nitrogen, argon and CO2), IG-100 (pure nitrogen) and IG-01 (pure argon).

5.      How does Clean Agent Suppress Fire

The chemical clean agents (HFC-227ea (FM-200™), HFC-125 (ECARO-25®) and FK-5-1-12 (Novec™ 1230), all extinguish a fire by the same mechanism (largely by heat absorption) and they all have the relative same degree of effectiveness.

Inert gases extinguish a fire by reducing the oxygen level down to a level where combustion cannot be sustained, typically around 12%. They all put out fires with equal effectiveness.

6.      Clean Agent Selection Criteria

How does one decide which agent to use in a given application? As might be expected, the answer to this question is not simple. It depends on many different factors, and the relative importance of each factor to the end user. These factors include environmental concerns, cost, design flexibility, acceptance by local & international authorities, operation and maintenance issues, and a multitude of other factors.

7.      Environmental Impact of HFC

8.      Environmental Impact of FK-5-1-12

9.      Environmental Impact of Inert Gas

10.  Environmental Impact of Different Clean Agent- A Graphical Presentation

Halon is a Monobrotrifluoromethane with very high ozone depletion properties. Its production was banned in 1994 under the Clean Air Act. While it is still legal to purchase and use recycled Halon, eventually, the diminishing supply will require businesses with halon-based fire suppression systems to replace their Halon systems with systems that use readily available alternatives such as Inert gas, Novec 1230 fluid and FM-200.

FM-200 – a hydrofluorocarbon (HFC) – was the first replacement for Halon that promised no impacts to the ozone layer. It is important to note that there are no regulations against using FM-200. It is still manufactured and widely used in clean agent fire suppression systems. However, the increasing concern over global warming has given rise to newer alternatives such as Novec 1230 fluid – the first clean agent on the market to boast no impact to the ozone layer or global warming – and IG.

11.  A comparison of Operational Aspect of Different Clean Agents

12.  A comparison of Agent Requirements

Considering a protected space of 836m³, Class C hazard, Design Standard NFPA 2001

13.  Installation Issue

Inert gas systems take up more room, and that space has a cost. They need to displace more air to put out a fire than an advanced clean agent like FM-200 / Novec 1230 fluid.

FM-200 fire suppression system is typically less expensive than a Novec 1230 system. When considering the entire cost, it's important to consider not just the amount of space to protect, but also the amount of storage needed for the cylinders. Novec 1230 needs slightly more of the compound to protect the same size space as FM-200, which means that the Novec system may need more cylinders which will take up more storage space and ends up adding to the overall cost.

14.  Recommendation

To select clean agent gas suppression system one should contact with professional engineering firms and in Bangladesh we, the Axis Safety Engineering is designing, supplying, installation and post installation services. Fore more detail please contact.

Engr. Md. Shahjahan Alam

B. Sc. Engg. (Mech/BUET), MBA, M.Sc. in Env. Sci. FIEB/11322, LEED Green Associate

Chairman- Axis Triangle Group

Chairman- Sajan Metal Industries Ltd.

Principal- Zohura Memorial Technical School

National Consultant- Dhaka Metro Rail Line 5 (Northern Route)