The Town vs. The Fire Department: The Determination Of Fire Risk Levels

At some point after identifying the level of fire risk in your community, you will have to address the most serious question of all: Just how much fire protection is needed to address the risk?

Before going any further, an important distinction must be made. The fire protection system in any community consists of several components. Each component has a role to play in keeping citizens safe from fire, and none should be ignored.

The suppression arm of the fire department is only one part of the equation. Public fire safety education, code enforcement, fire prevention inspections and installed private fire protection devices all contribute to the level of safety in any community. Each must be supported to the maximum extent possible.

Other agencies play parts in a community fire protection program. The support of government officials is essential; it is their control of the purse strings which we need to win for our efforts to be successful. The building department can assist in upgrading and maintaining the structures in every jurisdiction. Advice from attorneys can help to avoid problems in the development of legal remedies to lapses in protective remedies. A planning department serves as an important guide to the future. What types of building are currently permitted or might be in the future? How many people currently live in the community? What projections for the future exist?

These and other groups should be brought into your efforts. They can all be of assistance in providing a proper level of fire protection. Whether they have a statutory role or not is of little consequence. Having them buy into your team concept of fire protection is critical. They can raise your level of protection, and it may not even have to come out of your budget.

To protect a given level of risk, we must first know what level of fire protection is available to perform this function. If we are measuring risk in terms of fire flow, we must assess our capabilities in comparable terms.

This is the suggested methodology recommended by the National Fire Academy in its "Fire Risk Analysis" course. As part of this program, it urges you to use gallons per minute (gpm) to estimate suppression capability. The academy suggests this approach because it allows for direct comparison with the gpm fire flow demands that you have calculated for your target hazards.

This mechanism of comparison is useful because it can be utilized in a wide variety of circumstances. It also provides an actual mathematical determination as to whether a fire department can achieve the required level of protection.

The same two fire flows which were determined for the target hazards must be addressed for fire department suppression capability. The following department flow capabilities must be determined for analytical purposes:

  • Initial attack flow delivery capability.
  • Sustained attack flow delivery capability.
  • The provision of sufficient personnel to perform the support functions ancillary to the delivery of fire attack flows.

The initial attack flow can be determined by a study of actual fire company operations on the drill ground. We strongly recommend that NFPA 1410 "A Training Standard on Initial Fire Attack" be used as a guide for evolutions.

To provide a realistic appraisal of any fire department's capability, an appropriate response time must be determined. We must consider all of the time needed to discover the fire, report it to the fire department and have the department respond.

The National Fire Protection Association's Fire Protection Handbook states "it is generally considered that the first-arriving piece of apparatus should be at the emergency scene within five minutes of the sounding of the alarm, since additional minutes are needed to size-up the situation, deploy hoselines, initiate search and rescue, etc."

To more closely approximate the real world, the National Fire Aca-demy has determined that the initial attack capability is to be measured after 10 minutes. This allows five minutes for turnout and response, then an additional five minutes of operational deployment time. We would suggest that rather than conducting responses to actual buildings with apparatus and personnel, approximations be made. You need to determine:

  • Average time needed to process an alarm.
  • Response time to your identified target hazards.
  • Time variations for the different fire stations.
  • Time variations for the companies due to respond.

Response time information to certain districts may be available and could be used for this purpose.

When we perform a municipal risk survey, we always suggest the same approach. Trials are conducted using a drill ground, training facility or someplace where a safe trial can be held. Using a stopwatch, apparatus can begin to work at appropriate intervals based upon the pre-determined times.

Apparatus would begin to operate at staggered times based upon their designated arrival times. At the 10-minute mark, the amount of water flowing, in concert with the number of personnel delivering the fire flow, is recorded based on these criteria:

  • The number of 200-foot hoselines each manned by two personnel in protective clothing.
  • One pump operator for each pumping engine.
  • Minimum of two personnel for search and rescue. (An additional two people for each 2,000 square feet of occupied property must be factored in for larger buildings.)
  • One person for support functions, such as forcible entry and utility controls.
  • A minimum of two people for ventilation. (In situations requiring roof top ventilation, these two people must reach the roof location within 10 minutes.)
  • One person must be available for command.
  • One person to be safety officer.

1 1/2 - inch line 100 gpm
1 3/4 - inch line 150 gpm
Two - inch line 200 gpm
2 1/2 - inch line 250 gpm
(Must have three properly attired personnel.)

The evaluator will record all appropriate observations. This is done to determine the operational capability of the department. It is also used to ascertain the level of fire suppression resources which can be delivered at the 10-minute mark.

With the sustained attack flow, a paper analysis of the department and its water supply is usually sufficient. Owing to the logistical problems of developing a large sustained attack flow, this is an earlier approach. This is also done because most jurisdictions will not want to disturb mutual aid fire units for the water delivery capabilities that are needed in excess of their own. However, periodic large mutual aid drills can be conducted to confirm hypothetical figures and meet various requirements.

Suppose we have determined that a target hazard exists with an initial attack flow requirement, within its largest open area, of 750 gpm. During the drill ground simulation, you find that at the 10-minute mark, the following situation exists:

  • A 1 3/4-inch hoseline is operated by two personnel wearing full protective equipment (including self-contained breathing apparatus). A pump operator is at the pumping engine.
  • A crew of two people is searching the 4,000-square-foot building.
  • One person is in the building with a search crew for forcible entry.
  • Two people are on the roof performing ventilation.
  • A fireground commander is in place to control the operation.

Is this a force sufficient to protect the property? NO, because where a flow of 750 gpm is indicated by the flow formula, only 150 gpm is available. Where two people are searching, four would be required. There-fore, we have a deficiency of 600 gpm and insufficient firefighters to deliver water and search the building. At this point, there is an unprotected risk level of about 600 gpm in the initial attack formula for the target hazard.

How is this shortfall to be addressed? The answer lies at the heart of the our next column. We are going to begin studying how you go about developing a community fire defense program.

Over the past few columns, our discussions have centered on the need for tailoring fire protection delivery systems to the actual needs of the community. The subject of fire risk has been presented as it relates to the delivery and consumption of a community's fire protection resources.

The concept of using fire flow required for protection to determine levels of risk was introduced, as was the measurement of fire department resources in a comparable form. The interplay of these two concepts in the analysis of actual community fire risk sets the stage for understanding how a community fire defense program is developed. It is crucial to meet actual requirements, based on a solid, mathematically provable format.

Harry R. Carter, Ph.D., a Firehouse® contributing editor, is a battalion chief with the Newark, NJ, Fire Department and past chief of the Adelphia, NJ, Fire Company.