Whiteboard Drawing 2: roof ventilation

Whiteboard drawing detailing roof operations

The drawing above briefly summarizes the roof operations my crew has been training on over the last couple shifts.

By using two roof ladders, firefighters are able to safely cut a vent hole without needing to step off the ladder.

In the drawing, the first firefighter (top left) has finished their cuts and has started to open the roof. The second firefighter (bottom center) has just finished the bottom cut, and is handing the saw off to the lieutenant, then the two firefighters will work together to open the hole with hand tools.

Detail

Another important note is to never lean/pull or put your weight on a chimney, for obvious reasons.

Detail

Whiteboard Drawing

Through the floor firefighter rescue

I read a Fire Engineering article by Chris Piepenburg, then summarized it by illustration. The magic of a whiteboard drawing is that it is only temporary...... unless of course you take a picture of it.

Nicaragua July 2012

Rivas Bomberos in front of the WI engine.

This July I was fortunate enough to spend a little time with some firefighters (bomberos) in Nicaragua. Despite a language barrier, I felt at home with the firefighters of Rivas and Managua, finding that once we started to talk shop, I could communicate effectively with sound effects and emphatic gestures. 

Pumper from Canada

Most of Nicaragua’s fire equipment is inherited from other countries, especially the U.S. and Canada, so they’re working with nozzles and pumps I am familiar with. In fact, one of the trucks at the Rivas station was from Buffalo County WI, which just goes to show how small this world really is.

Fire Station in Rivas

While I was visiting the Station in Rivas I met Cesar Guevara, a Captain of the fire department in Managua, and in charge of Ambulance operations there. On top of that he was a doctor, and spoke English, relieving my friend Riley from her interpreter duties. Thanks again Riley. 

Captain Guevara had brought an ambulance from Managua to staff the medical station at the international master’s surfing competition, and stopped in the Rivas Fire Station to pay his respects. This was incredibly good luck for me, as I was invited to come shadow on the ambulance for the surfing competition.

Ah, the fantastic views offered at an international surfing competition.

 

While watching surfing and taking patients to the nearest clinic for stitches (nothing major) was cool, the best part of the competition was being able to talk to Captain Guevara.

I’ll briefly breakdown some of the firefighting numbers/facts he gave me.

Nicaragua is protected by a government fire department, within which there are professional and volunteer firefighters. This is a country wide system, meaning that there isn’t a Managua Fire Department, or a Granada Fire Department, instead they are all one organization. The exception to this is some volunteer departments, like Rivas, which do not operate under the Nicaraguan government fire organization. 

Although the fire service’s budget is small compared to Police, Immigration, or the Jail system (all four of these systems operate under one branch of government) only the firefighters are popular with the people. I guess some things are the same no matter where you go.      

Bomberos (firefighters) work for 48 hours, then have 48 hours off, work for 72 hours, get 72 hours off and then start back over again with the 48s. So they are at work half of the time.

Nicaragua has a population of roughly five million. During the day (when people are at work) the city of Managua swells to hold two million of those people. And they have seven fire stations. Which isn’t very many…. At all. 

In the end I didn't get to spend nearly as much time with the Bomberos as I would have liked, so hopefully I will return to Nicaragua before too many years go by. Maybe I'll learn Spanish too, who knows.  

Risk/Benefit (Nicaragua 2012)

Captain Guevara and yours truly.

 

Since talking to Captain Guevara, one comment he made has stuck with me. He said, because of the people’s financial situation, he and his firefighters, would take a greater risk while fire fighting then we would/should in the U.S. 

Emergency responders around the world use a system called risk/benefit to evaluate if they committing lives and resources appropriately for different situations.

It works like this: Risk nothing if nothing can be saved. For example, if flames are blowing out of ever window of a house, there is nothing left to be saved, so no action which puts firefighters in danger should be taken. On the flip side, if we know that someone is trapped in a building, we are willing to take great personal risks to help them. Usually the way this breaks down for the U.S. is, lives are worth serious risk to firefighters, whereas viable property is only worth a very small risk. You can buy a new refrigerator, you can even build a new house, but you can’t bring people back to life.

But what if you can’t buy a new refrigerator? Because it took you three years to save up for it, and now your income is barley enough to send your kids to school. What if you can’t build a new house? Because it’s the house your family has lived in for four generations. Unlike the U.S. insurance is pretty much unheard of, especially for the general population. When you lose something, it’s gone. As for a safety net for people that have a fire or a flood? It doesn’t exist.

Captain Guevara’s point was: While they use risk benefit, things have different weights on the Nicaraguan scale then they do in the U.S. He is willing to take serious risks save a closet or even to pull an appliance from a burning building, because those things are so hard to replace.

It raises a difficult question. If U.S. firefighters respond to a fire in the home of a poor family without insurance, should they use more risky/aggressive tactics then would for a family with a good income and insurance? 

Food for thought. 

Drawing

Drawing for my friend's son Silas who just turned six.

Credit to Allie Boyat for the tiger idea.

Intro to the Fire Brigades of Ireland

Dublin Fire Brigade fire helmet with face shield lowered

 This December I went to the Republic of Ireland to tour some of it’s fire brigades and learn about compartment firefighting. I ended up visiting four stations in Dublin, and five other cities’ fire brigades: Waterford, Limerick, Cork, Killarney and Galway.

Limerick Fire Station

Basically I would show up, ring the bell, introduce myself as an American Firefighter, and request a quick tour. This was a verbal Trojan horse to get me though the door, once inside I would proceed to pick their brains for everything they knew about compartment firefighting. Fortunately, I never met and Irish firefighter who wasn’t happy to share what they knew with me, so this strategy was very effective. I will get into the specifics of what I learned in future entries, but a brief summary of my experience in Ireland would be as follows.

The Fire Service in Republic of Ireland is very uniform, equipment, training operation and attitude were
consistent across the country. There are no volunteer firefighters in Ireland, but the majority of firefighters are paid-on-call. Meaning they do not staff the fire station, but when they attend training or respond for call, they are financially compensated.

All the firefighters I met were enthusiastic about their profession, and could fluently talk about their brigades' tactics and training. Compared to Americans, the Irish have very specific ways they try to accomplish different operations, and detailed protocols regarding safety and accountability. Though our counties equipment differs greatly, the most significant difference I noticed was attitude. I will write more on these subjects in later entries.

Crest of the Cork City Fire Brigade

This was a successful trip, thanks mostly to the Irish’s well known hospitality. I hope you will enjoy the rest of my entries.

Different Dragons

Why can't we apply European firefighting tactics in the U.S.? 

When I did ride-alongs with the Copenhagen Fire Brigade this past May (2011), I got my first taste of “Three-Dimensional” or “Compartment” firefighting. I was struck by the stark contrast between American and European fire tactics, high-pressure/low-flow vs. low-pressure/high-flow, for example. The question which arose for me was “why can’t we use European firefighting strategies in America?” because their strategies stuck me as more precise, scientific, and much easier to perform.  

I suspected that the differences in our tactics were rooted in our fires, and that our buildings were changing the fires. So far I was on the right track, but then I got off target. I keyed in on the different materials we construct our buildings out of, Denmark for example has very strict limits of what can be used in a structure and what cannot. In contrast, American builders can use just about any materials they want. However, as I learned, the material difference between our structures accounts for only a small part of the large difference in our fires.

This past December (2011) I traveled to Ireland and learned it’s not what our buildings are made of that make our fires different, it’s how our buildings are put together. The "built environment" changes both how the fire develops and potential options for engaging it.

A typical home in Ireland is divided into many small rooms separated by doors. It has no basement. Balloon frame construction (where exterior wall studs run from the foundation to the top floor creating hidden channels in which the fire can travel vertically through the structure) is not used. American homes are larger, typically have basements, and most significantly, open floor plans with large interconnected rooms.

Typical Irish Home

First floor plan of larger american home with open floor plan. Note the interconnected rooms. 

A fire can be classified as one of two types; these are ventilation-controlled and fuel-controlled. An example of each would be as follows: fuel-controlled, fire starts in a set of curtains, consumes them and goes out before catching anything else on fire. The curtain fire was fuel-controlled because it had plenty of O2 but it ran out of fuel, the curtains, and died. A ventilation-controlled fire develops in a room, and because of how furniture and materials are positioned in the room, the fire has all the fuel it needs and grows until it has exhausted all the O2. In Ireland most fires are ventilation controlled because they start in a small closed compartment (room) with a limited quantity of O2.

If a fire grows with enough fuel and O2 at its disposal, it will likely reach a state of development called "flashover". Flashover can be defined as the point in which all the combustible surfaces in a compartment are burning. It’s very difficult for a fire to reach flashover in a small closed compartment, for example a room in an Irish home, because of the limited amounts of O2. 

Irish Fire Brigades usually fight fires which haven’t flashed over, and remain confined to one room. Appropriately, their strategies, tactics and equipment are oriented towards engaging this type of fire.  In America, fire reach flashover frequently and when they do, quickly migrate throughout the structure.

Fire almost at flashover, note that some materials at the bottom of the compartment are not yet burning but have begun to off-gas (smoke)

So, that covers the differences between our fires, now let's talk about the tactics and strategies used to fight them. In the US, we use a larger diameter hose with a high gallonage stream, which gives us a lot of penetrating power and the ability to apply water from a greater distance. Aggressive fire attack is combined with ventilation, either vertical or horizontal. Vertical ventilation is when you cut holes in the roof of a burning structure, allowing smoke and hot fire gasses to escape. Horizontal ventilation is done by taking windows out. The goal of either type of ventilation is to release heat and fire gasses from the structure, making the inside more hospitable and improving visibility. America’s higher water flow is needed to deal with a more developed fire. Simply put, as the fire’s size and heat increases you will need more water to extinguish it. This strategy has two disadvantages. Water damage: more water flow equals less control, equals more water ending up not on the fire. Accelerated fire growth due to ventilation: while improving the environment inside the structure, ventilation also accelerates the speed of combustion and fire growth.

Vertical ventilation

In Ireland firefighters use a high pressure stream which has limited reach and flow. However, because the stream is at such a high pressure, the water is broken into small droplets which absorb heat quickly. Irish firefighters advance into the structure applying short pulses of water to cool the ceiling area and prevent the fire from extending above and behind them. Once they find the fire room they have a procedure for mitigating backdraft or re-ignition of the compartment by quickly opening the door a small way and applying short shots of water. No ventilation is performed until the fire is completely knocked down, because in an Irish home, the fire is typically ventilation controlled and they want to keep it that way. The smaller rooms limit the distance a stream of water has to reach. Additionally, fire gasses are confined to a smaller space, and water, once converted to steam, remains trapped in the compartment, occupying the space the fire wants to be in.

The Pros and Cons of American and Compartment Firefighting

American Fire Tactics

Pros: 

• Water streams have excellent reach and penetrating power, allowing water to be applied from a greater distance.
• By ventilating a burning structure, attack and search teams can work in environments which would otherwise be unbearable, even with turnouts and SCBA.

Cons: 

• Water damage is significant. 
• Larger hose is difficult to maneuver.
• A compartment or structure which needs ventilation will be pressurized with smoke and fire gasses. By releasing those gasses, you lower the pressure inside, drawing in fresh air. This is a mixed blessing, because while it may provide breathing air to victims, the influx of O2 rich air will accelerate combustion.   

Compartment Fire Tactics

Pros: 

• Small high-pressure lines are easy to handle and advance quickly. 
• Water can be applied with near-surgical precision, minimizing damage. 
• Small water droplets convert to steam quickly, absorbing a tremendous amount of heat. 

Cons:  

• In a larger compartment, steam doesn’t stay confined to the area to interrupt combustion.
• The reach of the low volume stream is limited, especially if it’s being used on a wider pattern, requiring firefighters to get much closer to the fire. 

In conclusion, the reason we do not use compartment firefighting tactics in America is because they're tailored to engaging ventilation controlled fires in small compartments. In America we often encounter fires which are relatively uncontrolled and are burning in multiple interconnected spaces. The low-flow/high-pressure hose is a surgical tool for fighting a specific type of fire, to take it into a lightweight American home with an open floor plan would be like charging into battle with scalpel. 

Although compartment firefighting as a whole may not be applicable to the American fire, there are still many lessons European and American firefighters can learn from each other. These tricks of the trade and solutions to common problems interest me, and I hope to learn more of them as I continue to travel. 

I would like to thank S/O John Chubb of the Dublin Fire Brigade, for taking the time to sit down and go over this with me. It meant a lot, and was absolutely the highlight of my time in Ireland.