Balance

Viewpoint: Balance

By Laura Blaul | Fire Protection Engineering

Ask any fire marshal, or most other fire service professionals, what's the surest way to prevent fire deaths and injuries, and limit property damage, and you'll most likely hear "automatic fire sprinklers," particularly in residential occupancies. But ask them what they're willing to give up for them, and the response will vary widely.

 

In an effort to increase fire sprinkler protection in buildings and homes, fire service officials have commonly offered incentives, to both property owners and policymakers, hoping to convince them to add systems voluntarily or make installation mandatory via local ordinance. "Trade-offs" commonly include decreased fireflow and fire main sizes, increased fire hydrant spacing, longer and narrower emergency access roadways (more time and fewer emergency response vehicles probable), and limited/ surgical decreases in fire-resistant construction. But where should the line be drawn? How much is too much?

 

 

The question of balance between passive and active fire protection is an old one and appears to be supported with more personal experience and opinion than science. Many in the fire service have a sense of satisfaction with the movement toward more fire sprinkler protection in buildings and those taking advantage of the increased design flexibility find the cost palatable. Yet when faced with significant change and choice for the first time, it is often realized that there may be more to the safety equation than initially recognized. The process involved in reaching a determination is likely similar to the one used when evaluating performance-based designs maybe newer for some than others, but no less daunting.

 

 

In California, the development process for the state version of the International Building Code and International Fire Code is underway. The increased size of buildings protected by fire sprinklers, in height and area, as well as the decrease in fire resistance of several building components, is several times that permitted under the Uniform Codes. This has forced building and fire code officials, along with other stakeholders, to take a closer look, which has proven more difficult than expected.

 

 

As of yet, there is no consensus of opinion, and there are limited data upon which to draw. There appear to be more unanswered questions than facts:

  • Which code had it right? The three model codes had different base values and approaches for determining building size, but none can clearly and objectively tout value beyond historical relevance. Even regional fire loss data are lacking scientific value. The new codes combine regional approaches, resulting in base values and formulas that allow larger buildings than constructed anywhere in the nation.
  • What is the true reliability of automatic fire sprinkler systems? The data are limited and questionable. Much of it relies on surveys and incident data completed by fire departments (often incomplete and inaccurate, if even returned). A recent paper by William Koffel (Jan. 2006) attempts to reconcile operational and performance reliability, and concludes that the overall reliability is 89 percent. How should that information be used? Local experience related to enforcement of maintenance requirements, percentage of system "downtime" (for TI work, maintenance, etc.), arson rates (e.g., 25 percent of determined fires in Orange County, California, compared to 10 percent nationally), mechanical failure, and disruption in water supply all play still unknown roles.
  • What about areas of higher seismic activity? Should there be an adjustment in the height and area formulas in regions where earthquakes are a more probable occurrence, or does the structural and system seismic design adequately account for this? What scenarios and factors are reasonable to consider? Supply disruption with fire? Conflagration?
  • How should the existing fire protection infrastructure be considered? Should a region's municipal water supply or fire department resources, equipment, and/or capabilities/tactics play a role in the decision?

There's even been debate about the purpose of the building code is it life safety only or is property protection an equal goal? And, as with performance-based design, how does one determine the (unstated) fire protection goal? The California State Fire Marshal delivered the charge that California will retain an equivalent level of fire and life safety to that which is enjoyed today, when evaluated from an holistic perspective. Determining acceptable loss is a daunting task and one that must consider the variety of factors that contribute to community safety and prosperity.

 

 

Lacking the data and science needed to understand the ramifications of decisions, one is left to opinion and conjecture in identifying the correct balance. Is redundancy a waste of money or a prudent safety feature? Can the U.S., with one of the highest per capita fire rates of any industrialized nation, afford to gamble? It is the author's hope that it doesn't take the next few years to find out.

 

 

Laura Blaul is with the Orange County (CA) Fire Authority.