Letters: Reader Feedback
Kudos for commissioning; Ethics talk excellent The article "Diary of a Commissioning Agent" (CSE 11/05, p. 29) by Joseph Sather is excellent. This is a perfect testimonial on why commissioning of equipment is so important. It is also very typical of how difficult it can be to make additions to or modify the infrastructure of a health-care facility.
Kudos for commissioning; Ethics talk excellent
The article "Diary of a Commissioning Agent" ( CSE 11/05, p. 29 ) by Joseph Sather is excellent.
This is a perfect testimonial on why commissioning of equipment is so important.
It is also very typical of how difficult it can be to make additions to or modify the infrastructure of a health-care facility.
Your November Editor's Viewpoint ("Don't Forget Ethics in the Fundamentals Kit," p. 5) is also great.
So many people seem to forget their ethics when money or politics are involved.
JEFF KIPFINGER, P.E., TLC ENGINEERING, ORLANDO, FLA.
Loved your editorial in the November issue concerning ethics!
The electronic version of the magazine is great and the content is excellent. Keep up the good work.
THOMAS W. GARDNER, P.E., SCHIRMER ENGINEERING CORP., DULUTH, GA.
Clearing the air on clean agents
Articles such as Kenneth Gentile's "Life After Halon" ( CSE 11/05, p. 58 ) are excellent methods to communicate important information to those responsible for halon replacement and for specifying alternative methods to replace the important role halon has played in critical-asset protection. The author does a good job in furthering the discussion, and I applaud him and others who take the time and effort to do this. It can be daunting for those not directly involved to make sense of the halon phase-out, understand the roles and limitations of the alternatives and apply this information when specifying sustainable fire protection. That said, there are a number of points in the article that must be clarified.
I am a principal member on the NFPA 2001 committee. As do my colleagues on that committee, I regularly answer general questions regarding the clean-agent industry and, given my position at 3M, our product in particular, Novec 1230 fluid. So I wish to take the opportunity to comment on several points.
First, the accepted definition of "clean." A clean agent may certainly result in minimal damage to the environment, but that is not the reason it is considered "clean." The definition of a clean agent in Chapter 3 of the 2004 edition of NFPA 2001 describes physical characteristics. To quote:
3.3.6 Clean Agent. Electrically nonconducting, volatile, or gaseous fire extinguishant that does not leave a residue upon evaporation. The word agent, as used in this document, means clean agent unless otherwise indicated.
Later, in describing clean agents, a reference is made in the article that clean agents leave "little or no residue." This was particularly disconcerting as that statement resulted in a number of inquiries from—and ensuing reassurances to—concerned customers of multiple OEMs regarding exactly what remains when a clean-agent system discharges. The answer is: no residue. Referring back to the definition, a clean agent "does not leave a residue upon evaporation after a system discharge."
This is an extremely important point, as it was enough to compel concerned customers to request clarification. When it comes time for those customers to make a significant investment in a clean-agent fire-suppression system for critical assets, they cannot tolerate such residue. There is a "performance expectation" inherent in the term clean agent, and one must refrain from attributing characteristics that don't apply.
A third point: In the section "Design and Cost Considerations," the author referred only to two subjective factors that affect selection of the type of agent and system: cost and specific agent characteristics. Not included along with those two considerations was a third key: the agent's environmental impact. This frankly was the motivation for the phase-out of halon under the Montreal Protocol. Rather, the author relegated that to "other considerations," implying, to me, a lesser importance.
The fact is, environmental considerations—i.e., ozone depletion and global warming—are increasingly driving the decision-making process that end users and specifiers employ to choose a particular solution. Corporations that have facilities in many countries—and the consulting fire-protection engineers they engage—find themselves increasingly compelled to take a global view on what seemingly is a local issue. When multinational businesses specify a protection method, they do so in a similar fashion as they would any particular corporate process or method. They are reluctant to do so in a piecemeal fashion. Rather, they are more inclined to choose a fire-protection solution that provides the least business risk overall while avoiding exposure to future regulations, regardless of location. Specifiers need to be sensitive to this growing need from multinational clients. Returning to NFPA 2001, Chapter 1 definitively requires consideration of the environment when choosing a clean agent.
1.6* Environmental Factors. When an agent is being selected to protect a hazard area, the effects of the agent on the environment shall be considered. Selection of the appropriate fire suppression agent shall include consideration of the following items:
Potential environmental effect of a fire in the protected area.
Potential environmental effect of the various agents that could be used.
And, from the Annex, there exists explanatory material:
A.1.6. Many factors impact the environmental acceptability of a fire suppression agent. Uncontrolled fires pose significant impact by themselves. All extinguishing agents should be used in ways that eliminate or minimize the potential environmental impact. General guidelines to be followed to minimize this impact include the following:
Do not perform unnecessary discharge testing.
Consider the ozone depletion and global warming impact of the agent under consideration and weigh these impacts against the fire safety concerns.
Recycle all agents where possible.
Consult the most recent environmental regulations on each agent.
The unnecessary emission of clean extinguishing agents with either the potential of ozone depletion or the potential of global warming, or both, should be avoided. All phases of design, installation, testing and maintenance of systems using these agents should be performed with the goal of no emission to the environment.
Finally, corrections to Tables 1 and 3 in the article are also necessary. In Table 1, the modes for FE-227 and Novec 1230 should read, "Extinguishes primarily for cooling." I would change comments on Novec 1230 to read, "Established agent available in the market from major systems manufacturers."
In Table 3, the description for FM 200 should read: "Typical use concentrations at or below NOAEL. Use of PBPK (Physiologically Based Pharmacokinetic) model required when used above the NOAEL. Frostbite possible if too close to nozzle."
I also feel the description of the environmental effects of each agent should be amended as follows:
Inergen: The atmospheric lifetime (ALT) and global-warming potential (GWP) should both show a value of zero.
FM 200: ALT = 33 years and GWP = 3,500.
Novec 1230: ALT = five days, GWP = 1.
The ozone-depletion value for each agent is zero.
Finally, the clean-up for Novec 1230 should be the same value as the other two agents: "Ventilate, no residue."
Again, I applaud Mr. Gentile for taking the time to present this article as a means for generating discussion. Hopefully, this and other articles like it continue to shed light on a very complex and dynamic clean extinguishing agent industry while helping dispel recurring misconceptions in the industry.
PAUL E. RIVERS, P.E., 3M FIRE PROTECTION, ST. PAUL, MINN.
Author Ken Gentile responds:
I wish to thank Mr. Rivers for the valuable supplemental information to that provided in my original article. First, by providing the specific NFPA 2001 definition for "clean agent," he correctly calls attention to the common inference that the terminology "clean" applies to environmentally compliant systems. All halon replacements that comply with NFPA 2001 are "clean" in both the environmental and residue considerations. The current vernacular is not technically correct when applying the term solely to the agent's environmental characteristics.
While Mr. Rivers' discussion on the environmental considerations in selecting a clean agent is certainly insightful, the focus of the article was to provide general information to facility and design engineers. Experience shows that where environmental performance determines selection of an agent, the decisions are made as policy criteria that are typically beyond the responsibilities of facility and design personnel.
Concerning the proposed revisions to Table 1's Mode criteria for FE-227, this may be a matter of emphasis and semantics. Dupont literature describes the extinguishing mode as follows:
The dominant factor is the ability of FE-227 to absorb, at the molecular level, the heat energy from the combustion reaction. When heat is absorbed, the reaction cannot sustain itself and combustion ceases. Fires in atmospheres containing FE-227 are prevented or extinguished at a lower concentration of agent than predicted by heat capacity calculations. This is attributed to the ability of FE-227 to form free radicals, which chemically interfere with the chain reaction combustion process, thereby aiding extinction.
Similarly, Fike literature describes the extinguishment to be by "a combination of chemical and physical mechanisms."
As a representative of 3M, the manufacturer of Novec 1230, Mr. Rivers' information concerning that product is more current than that provided in the article, and is a welcome addition.
Finally, I wish to thank Mr. Rivers for providing the specific environmental standards and indexes as backup to my "man-on-the-street" verbiage in Table 3. As with the other information he provided, it added to a richer, more complete discussion.
KEN GENTILE, P.E., SENIOR CONSULTANT, ROLF JENSEN AND ASSOCS., HOUSTON
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