Fog Nozzle Training: Are We Creating a Hazardous Impression

BY MICHAEL L. WALKER

When teaching firefighter recruits, it is common for instructors to come up with catchy phrases and acronyms to help students remember the point of the lesson. For example, when we teach fire extinguishers, we use the acronym PASS, which stands for Pull, Aim, Squeeze, and Sweep. We teach COAL WAS WEALTH for size-up and RECEO VS to emphasize tactical priorities. Another learning device sometimes used when teaching how to adjust a fog nozzle to achieve a particular nozzle pattern is “Right for Reach/Left for Life”: If the nozzle is rotated to the right, a straight stream is produced; if the nozzle pattern is adjusted to the left, a fog pattern results. Although the adage is effective in the respect that it emphasizes which way to turn the nozzle, the second part of the statement can be interpreted by firefighters to mean that a wide fog pattern will protect a firefighter caught in a flashover.

Recently at an acquired structure live fire burn, the importance of checking the nozzle pattern prior to entering a structure fire was discussed with some firefighters who recently completed their Firefighter I academy. When the instructor for that day asked the firefighters which way to adjust a fog nozzle to achieve a straight stream, they recited in a cadence much like those saying the Pledge of Allegiance, “Right for Reach/Left for Life.” Inquiring further, the instructor asked the firefighters what that meant to them. They told the instructor they had been taught to adjust a fog nozzle toward the right to achieve a straight stream and to adjust it all the way to the left in case they were caught in a flashover. The instructor then asked them to clarify the rationale behind the wide fog angle concept. The students explained how a wide fog pattern provides protection from the heat and flames if the nozzle team were caught in a flashover. It would appear that these students learned their lesson well—maybe too well. 

“LEFT FOR LIFE” 

The origin of the “Left for Life” theory likely derives from multiple sources, including liquefied petroleum gas (LPG) or flammable liquid and gas (FLAG) classes, where a wide fog pattern is advocated. The common tactic used for this type of firefighting entails using two 1¾-inch handlines, both simultaneously advanced toward the fire with both nozzles on a wide fog pattern. The water stream acts as an effective shield from the fire as the students approach the roaring flames. You can see the fire attempting to pass through the opaque screen of water, but as long as the streams are wider than the flames, the streams provide a useful haven. With such a vivid example of protection portrayed in these situations, it is understandable how many would come to believe that this same level of protection would be adequate in any situation. But is that really the case? Will using a wide fog stream in a flashover situation protect firefighters inside a compartment?

To date, no factual scientific data exist to support that notion. The National Institute of Standards and Technology (NIST) has not performed tests evaluating the benefits of interior use of wide-fog patterns and their effect on firefighters in the immediate vicinity of a flashover. To my knowledge, no other credible institution has either. The closest scientific data that exist come from NIST’s recent research on wind-driven fires in high-rises. This research showed that a solid stream cooled a larger area better than a wide fog pattern. It also found that the solid stream cooled the area by as much as 20 percent faster than a fog stream.1 

LAYMAN’S THEORIES 

Much of the confusion about fog nozzles still derives from the misapplication of Lloyd Layman’s theories. When Layman developed the indirect attack, it was a good firefighting application for the day and times in which it was conceived. Firefighter bunker gear offered less protection, and self-contained breathing apparatus were all but nonexistent. Layman’s method allowed firefighters, who still primarily operated outside or very shallow inside a structure, to create much less water damage than smooth bore nozzles did from the same exterior position. For the indirect method to succeed, even back then, certain conditions had to be present. One of the requirements was limited ventilation, which kept all of the steam inside the compartment, thereby inhibiting combustion. Another element of a successful indirect attack was that no one was supposed to be inside the container. Layman emphasized this fact because the steam could kill anyone in the compartment.

Over the years, Layman’s original concepts have morphed into different methods, namely the combination attack and the most recent 3-D fog attack. This method, derived from European firefighters seeking safer interior firefighting methods, has become the main tactic used in Great Britain and by other European fire departments.

On raising the Right for Reach/Left for Life question to both Paul Grimwood and Ed Hartin, authors of the 3-D fog attack, they explained that the answer to this question is “a bit more complex than a simple ‘left for life’ explanation.” Both emphasize the importance of avoiding the flashover scenario by any means necessary. In his e-mail, Grimwood said:

We hope never to place our crews into such a situation. Having said all that I know, things may still turn to hell within seconds! The nozzle application you discuss MAY do something effective against a flashover; but yes, it will probably also ‘cook’ the crew. However, it is my view that when the gas layer ignites suddenly, instantly those involved become instinct-driven animals. They crawl over each other to find a way out. There is no easy method here. I will not stand and decry this technique, but neither will I support it!”

Hartin gave a much more technical explanation:

…if less than 35 percent [of the water] is vaporized, the hot gas layer, the total volume will increase. The reason for this is that water that passes through the hot gas layer and vaporizes on contact with the surface expands at least 1,700 times but does not substantially lower the temperature of the hot gas layer.

Both Hartin and Grimwood advocate using a narrower fog pattern and trust it for limited use. They believe that using a pulsed flow or penciling stream, so as not to overwhelm the environment, while making a hasty retreat is appropriate. Also, and most importantly to both of them, is to learn how to recognize and avoid being caught in a flashover in the first place.

The insight shared by Grimwood and Hartin brings to light the complexity of the flashover situation from both the human behavior and scientific perspectives. When the room flashes over, it is doubtful whether anyone operating the nozzle would have the presence of mind or the time to adjust the nozzle pattern. Once flashover occurs, those involved must make an immediate retreat using the nozzle pattern they were using prior to the event if they hope to survive.

On the other hand, if the firefighter were able to adjust the nozzle pattern, the use of a wide, continuous fog pattern would only exacerbate an already horrendous situation. As anyone who has participated in a training session inside a flashover simulator will recall, the final portion of the scenario is the “steam-out.” This entails the instructor’s demonstrating the effects of too much steam within a fire compartment by adjusting the nozzle to its widest setting and turning it on until the observation area fills with hot steam. Before this occurs, the students are warned so they can get as low as possible. This warning, of course, isn’t given in a real flashover. Also keep in mind that the small, predictable fire within a flashover simulator produces only a fraction of the British thermal units (Btus) generated in an actual structure fire and the nozzle used within a flashover simulator can generate only a portion of the gallons per minute (30) of the normal attack line. It would then stand to reason that the discomfort felt by students during a planned steam-out in a simulator would be minuscule compared with what would occur if the same tactic were employed in an actual flashover.

Back on this side of the pond, the debate between fog patterns vs. straight stream/solid bore use is alive and well. Depending on who is consulted, the answer to the “Left for life” question will vary. In February 2000, Fire Engineering published “Little Drops of Water: 50 Years Later, Part 1” written by Andrew A. Fredericks.2 The article contained interviews with many of the “fathers” of fog attack methods used in the United States. Among them was David Fornell, author of the Fire Stream Management Handbook. According to Fornell,

The interior indirect, or combination, attack as practiced by a large percentage of the fire service today was invented by the fire service itself to compensate for problems encountered employing techniques based on earlier self-invented principles. Nowhere in his writing did Chief Layman present scientific arguments that advocated spraying water over firefighters’ heads in a fire situation in order to create steam bath conditions. On the contrary, he said firefighters would be enveloped in a hurricane of water converting to steam.3 

Fredericks also cited Layman multiple times in his article:

Layman went so far as to discourage the use of doorways for fog application, as the outflow of scalding steam would be extremely debilitating to the nozzleman.” (2)

Layman also said in his book Attacking and Extinguishing Interior Fires, “An indirect attack should always be made from positions that will enable personnel to avoid injuries from super-heated smoke and live steam.”4

Since the days of Layman, many things have changed. Firefighters have changed their practices in that they primarily operate inside the structure, especially when the possibility of a rescue exists. Fire apparatus are faster than those of the 1950s, which means firefighters arrive sooner than before. Today’s 911 systems also contribute to faster response times. The fires have changed as well. Though many will argue nozzle patterns, none will argue the fact that today’s fires are much hotter than in the days of old. The Btu output of today’s fires, which consists primarily of petroleum-based products, intensifies faster than the output of fires encountered by Layman in the 1950s and 1960s.

The only advocates for the “Left for Life” theory I could locate were a few firefighters who had used a wide fog to cool the room when they felt it getting too hot. The concern with these limited testimonies is that none of the attesting firefighters were in an actual flashover. Interestingly, all of these same firefighters could also recall situations where they had been “steamed” by wide fog.

Although specific study data on the effects on firefighters of a constant wide-fog pattern during a flashover are currently nonexistent, other studies have determined the effects of steam on humans. The 17th edition of the Fire Protection Handbook states that “the effects of exposure to heated air are greatly augmented by the presence of moisture in the fire atmosphere.”5 In other words, steam causes the heat to be more destructive to humans, aka firefighters.

With all of this in mind, firefighters should be apprehensive about implementing a tactic that isn’t based on any credible data that speak directly to the method and that appear to be contraindicated by all periphery data. Being caught in a flashover may very well be the deadliest situation a firefighter will ever face; to use a steam pattern that worsens their situation is dangerous, and it approaches negligence if we teach it. For those still looking for a catch phrase, perhaps “Righty Tighty/Lefty Loosy” will appropriately serve, but teaching that a wide, continuous fog pattern will provide protection from flashover is without merit, and we should not teach it.

The methods devised in the past were appropriate for the type of firefighting employed when the majority of fire operations occurred from the exterior. However, because of the evolution of everything that pertains to firefighters, including the fires themselves, archaic practices must be replaced with techniques that are appropriate for the present. The best method of surviving a flashover is to know how to avoid it in the first place, but if firefighters should become caught in one, they should aggressively retreat from the area using a nozzle stream that won’t hasten their demise. Even those who advocate fog use for interior firefighting are concerned with the practice of using a continuous wide fog in a flashover. Excellent research proves that excessive moisture in a superheated environment amplifies the chance and severity of injury. To use a nozzle pattern that knowingly produces the maximum amount of steam within the fire compartment may stop flame production but will cause steam injuries that could make a deadly possibility an absolute certainty.

Endnotes

1. S. Kerber, D. Madrzykowski, NIST TN 1629, “Firefighting Tactics Under Wind-Driven Fire Conditions: 7-Story Building Experiments,” 6.

2. Fredericks, Andrew A., “Little Drops of Water: 50 Years Later, Part 1,” Fire Engineering, February 2000.

3. Fornell, D, Fire Stream Management Handbook, Fire Engineering, 1991, 84.

4. Layman, Lloyd, Attacking and Extinguishing Interior Fires.(Boston: National Fire Protection Association, 1952), 45.

5. Hartell, Gordon E., “Combustion Products and Their Effects on Life Safety,” Fire Protection Handbook, 17th Edition. (Quincy, Mass.: National Fire Protection Association, 1991), 3-9.

MICHAEL L. WALKER is a 20-year veteran of the fire service and a battalion chief with the Oklahoma City (OK) Fire Department. He has been a fire service instructor for 15 years.

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