Structures:

Structure Triage

We expect a lot from professional firefighters-justifiably so. Aside from fighting fires we expect firefighters to deal with hazardous materials, be emergency medical technicians and rescue treed cats. Some people expect them to be kamikazes as well-to rush in to defend every house no matter how exposed or ill-prepared it may have been. That is too much. Competence and bravery--yes, suicidal foolishness--no. If you expect a firefighter to risk injury or worse defending your house, you have to give him something to work with, and it wouldn't hurt to give him the incentive of a defensible space to work in.

Research on the subject shows that a few factors have a great influence on the survivability of a structure. These four are the main ones:

• ease of access to the property by firefighters
• roof construction
• defensible space
• the slope of the land

Firefighters are trained to evaluate the survival chances of structures threatened with fire. At a higher level, fire commanders have to consider how much risk it is wise for their crews to accept. Safety aside, firefighting resources are not easily replaced.

The following is from a paper prepared by a student at the National Fire Academy's Strategic Analysis of Fire Department Operations course (National Fire Academy, 1990):

"'Triage' originates from a word meaning to divide into three parts. Basically, it amounts to: 1) eliminate the hopeless; 2) ignore the unnecessary; 3) deal with the rest. While we, as firefighters, hesitate to write off any threatened structure, triage is necessary to prevent futile waste of effort. Trying to save more than you realistically can might very well result in the loss of everything, including homes you could have saved. Forget the structures that are impossible or too dangerous to defend; leave those that are too well involved to save. Ignore, for now, the structures needing little or no protection. Concentrate on seriously threatened but savable structures." (Brown, Structure Triage During Wildland/Urban Interface/Intermix Fires, 1994)

We who remember the '93 fire may by spoiled by the immense resources that were available in that case. The resources assembled for that fire were the largest ever assembled in the U.S.

The checklists provided below highlight the same factors firefighters will be using. You can make your own judgment about how much defensible space you can or want to provide, and your own guess about the firefighter's triage judgment.

On the following pages [in the print edition] you'll find two methods of evaluating the wildfire vulnerability of your home. They were developed by the Utah and Virginia State Departments of Forestry to provide property owners and professionals a quick but reasonable tool for the purpose.

The Utah rating scale [Figure 8 in the print edition of this study], requires a little explanation. "Slope Rating" is the slope of the land surrounding the building in degrees. "Aspect" is the direction in which the land slopes (level being no slope.) "Weather" is the number of days per year on which the local Fire Department declares critical weather. In our Santa Monica Mountains, 20-30 Red Flag days are declared per year. I don't know what the Utah criteria are for critical weather, but they probably are not far different from our Red Flag criteria which are: winds over 25 m.p.h.; humidity of 15% or less, and a burning index of 81 or more. "FD Resp" is the time in minutes of the local fire station.

The vulnerability total for any building is derived by reading down each column to the relevant line and picking up the number of points. The total points given by this system may be a little low because of the slow response time the Utah model expects, probably due to the low density of the rural population. In Los Angeles County, even before the fire "season" has begun in August or September, a brush fire call will be bring a response from multiple stations and helicopters, typically in under ten minutes.

The Virginia Vulnerability Assessment form [Figure 9 in the print edition of this study], is reasonably self-explanatory. Filling in the blanks and adding up the points will give you a rough idea of the fire vulnerability of your home. A point total of 0-19 points suggests low vulnerability; 20-39 points suggests medium risk; and 40-60 points suggests something needs to be done.

Applying both systems to your home will give you a reason to look at your place with open eyes, which can only be a good thing.