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Posted: Sep 13, 2017

Why Vacuum: Understanding Fire Service Vacuum Apparatus and Comparisons with Conventional Apparatus

By Jason Estep

There have been many strides made in firefighting technology in the past 100 years.

At the beginning of the 20th century, firefighting equipment consisted of a steam-powered piston pump pulled to the scene of a fire by a team of horses. Once the apparatus arrived on scene, some type of water source had to be secured to effectively fight the fire. Modern day apparatus have evolved into high-horsepower, high-volume pumping machines that have tremendous advantages over earlier apparatus. However, one thing remains the same: Once arriving on scene, a water source still has to be established to properly extinguish the fire.

Drafting Operations

Since the majority of the United States is rural, many communities are not blessed with water systems, and if they are, they are often weak systems. Regardless of the reason for a feeble water supply, the fire department is still charged with the responsibility of properly controlling fires within its community. This has caused most fire departments in rural America to depend on streams, ponds, lakes, rivers, etc. to provide water for firefighting operations. The only problem is to get it from the source to the fire. To do this, tanker shuttle operations are set up. A tanker shuttle consists of individual trucks, usually with large tanks, transporting water from point A to point B.

1 A vacuum tanker can effectively obtain water at the closest source without the need for a fill site pumper and with minimal personnel. (Photo courtesy of Firovac.)
1 A vacuum tanker can effectively obtain water at the closest source without the need for a fill site pumper and with minimal personnel. (Photo courtesy of Firovac.)

The flow rate of a tanker shuttle depends on two variables: dump time and fill time. The Insurance Services Office (ISO) formula for travel time in a two-mile shuttle is a constant 35 miles per hour. To increase flow rates, departments began trying to lower the fill and dump time. Lowering the dump rate was easily accomplished by placing 10-inch Newton gravity dumps on trucks. The problem is you cannot dump what you have not first loaded. To decrease fill times, large quantities of personnel, hose, and at least one 1,250-gallon-per-minute (gpm) pumper must be committed to fill a tanker. As a rule of thumb, the fill site pumper will only be operating at 70 percent efficiency. Combine that with the fact that most conventional tankers have only one 2½-inch direct tank fill, and you can see the difficulty in reducing fill times. Now, examine the number of personnel needed to fill the conventional tankers. You must have a fill site pump operator; at least one person per tanker (in a large shuttle) to connect the hoses; one person tending to portable pumps/drafting operations; a driver for each tanker; and, in a large shuttle, more fill site pumpers to reduce wait time.

Next, let’s examine the setup time for a fill site operation. A drafting operation has to be set up, whether it is directly from a water source or from a dump tank being supplied by portable pumps. If portables are used, crews must take time to set them at the water source, stretch the lines, and get the dump tank set. Once the drafting operation is established, personnel must lay out fill lines along with any adapters or appliances needed to fill each tanker in the shuttle. This all has to be done when the attack crews are fighting the fire and needing the water the most: at the beginning. There is no doubt that after everything is set up, with enough personnel and trucks to establish an efficient shutt

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Posted: Sep 13, 2017

From the Neck Up

Robert Tutterow   Robert Tutterow

Full disclosure: I am not a big fan of how most of the North American fire and emergency services provide personal protection from the neck up.

Specifically, this includes protection of the head during nonfire activities - which is the bulk of our responses. Eye and face protection is extremely void of any defined or standard design application for nonstructural responses. This month’s column is intended to give you and the collective fire and emergency services something to think about.

National Survey

To underscore this disclosure, a national survey (6,655 respondents) conducted earlier this year revealed that 61 percent of firefighters use eye and face protection that is not provided with their helmet. Of those 61 percent, safety glasses were used by 83 percent of those respondents. There is minimal use of face shields and/or goggles that come with helmets. How can I say that? During FDIC International, I paid particular attention to the videos of the H.O.T. training evolutions that occurred on the days before the general sessions. And, I studied the hundreds of photos that lined the walls in the long corridor between the Convention Center and the Lucas Oil Stadium. With several hundred examples, I found only one occurrence of helmet-provided eye protection being deployed. Almost without fail, firefighters had chosen to disregard the face shields, flip-downs, and goggles that come with helmets. In fact, a significant number of firefighters were wearing helmets without any eye/face protection. What were they using? Safety glasses. Safety glasses provide far superior protection over the ineffective protection provided with helmet-supplied face and eye protection. They are form fitting, may be sunglasses, and may have corrective lenses. NOTE: For structural firefighting, the self-contained breathing apparatus face piece, combined with a hood, provides excellent eye and face protection.

Are there better alternatives? Perhaps. Many fire departments have already adopted a policy of issuing two sets of turnout gear to its members. Other departments are aggressively seeking funding to do likewise. Typically, the second set consists of a turnout coat, turnout pants, a hood, and maybe a pair of gloves. Rarely is a second set of boots or a helmet issued. Since this topic is titled “From the Neck Up,” boots will not be discussed.

However, there might be a slightly different approach to issuing a second helmet. That approach is to offer only one structural helmet but then offer another multipurpose helmet. But first, why issue only one structural helmet? Because the need for a structural helmet for actual fire suppression is not nearly as high as the need for head, face, and eye protection for nonactive firefighting activities. One structural helmet should suffice if the helmet has a removable head band that could be easily cleaned or if each member were offered a second headband. Cleaning a helmet outershell is not that complicated and typically does not require any special equipment.

A Multipurpose Helmet

The thought of a multipurpose helmet occurred to me when I had a chance to participate in the Scottish Fire and Rescue Services Symposium in Glasgow this past May. The sponsors of the Symposium were allotted tabletop displays. One of the tables displayed a helmet that was designed for urban search and rescue (USAR), paramedic, and water rescue. The only nonstructural application it did not cover was wildland firefighting. Perhaps it could be redesigned or modified for wildland.

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Posted: Sep 13, 2017

From the Neck Up

Robert Tutterow   Robert Tutterow

Full disclosure: I am not a big fan of how most of the North American fire and emergency services provide personal protection from the neck up.

Specifically, this includes protection of the head during nonfire activities - which is the bulk of our responses. Eye and face protection is extremely void of any defined or standard design application for nonstructural responses. This month’s column is intended to give you and the collective fire and emergency services something to think about.

National Survey

To underscore this disclosure, a national survey (6,655 respondents) conducted earlier this year revealed that 61 percent of firefighters use eye and face protection that is not provided with their helmet. Of those 61 percent, safety glasses were used by 83 percent of those respondents. There is minimal use of face shields and/or goggles that come with helmets. How can I say that? During FDIC International, I paid particular attention to the videos of the H.O.T. training evolutions that occurred on the days before the general sessions. And, I studied the hundreds of photos that lined the walls in the long corridor between the Convention Center and the Lucas Oil Stadium. With several hundred examples, I found only one occurrence of helmet-provided eye protection being deployed. Almost without fail, firefighters had chosen to disregard the face shields, flip-downs, and goggles that come with helmets. In fact, a significant number of firefighters were wearing helmets without any eye/face protection. What were they using? Safety glasses. Safety glasses provide far superior protection over the ineffective protection provided with helmet-supplied face and eye protection. They are form fitting, may be sunglasses, and may have corrective lenses. NOTE: For structural firefighting, the self-contained breathing apparatus face piece, combined with a hood, provides excellent eye and face protection.

Are there better alternatives? Perhaps. Many fire departments have already adopted a policy of issuing two sets of turnout gear to its members. Other departments are aggressively seeking funding to do likewise. Typically, the second set consists of a turnout coat, turnout pants, a hood, and maybe a pair of gloves. Rarely is a second set of boots or a helmet issued. Since this topic is titled “From the Neck Up,” boots will not be discussed.

However, there might be a slightly different approach to issuing a second helmet. That approach is to offer only one structural helmet but then offer another multipurpose helmet. But first, why issue only one structural helmet? Because the need for a structural helmet for actual fire suppression is not nearly as high as the need for head, face, and eye protection for nonactive firefighting activities. One structural helmet should suffice if the helmet has a removable head band that could be easily cleaned or if each member were offered a second headband. Cleaning a helmet outershell is not that complicated and typically does not require any special equipment.

A Multipurpose Helmet

The thought of a multipurpose helmet occurred to me when I had a chance to participate in the Scottish Fire and Rescue Services Symposium in Glasgow this past May. The sponsors of the Symposium were allotted tabletop displays. One of the tables displayed a helmet that was designed for urban search and rescue (USAR), paramedic, and water rescue. The only nonstructural application it did not cover was wildland firefighting. Perhaps it could be redesigned or modified for wildland.

Read more

Posted: Sep 13, 2017

From the Neck Up

Robert Tutterow   Robert Tutterow

Full disclosure: I am not a big fan of how most of the North American fire and emergency services provide personal protection from the neck up.

Specifically, this includes protection of the head during nonfire activities - which is the bulk of our responses. Eye and face protection is extremely void of any defined or standard design application for nonstructural responses. This month’s column is intended to give you and the collective fire and emergency services something to think about.

National Survey

To underscore this disclosure, a national survey (6,655 respondents) conducted earlier this year revealed that 61 percent of firefighters use eye and face protection that is not provided with their helmet. Of those 61 percent, safety glasses were used by 83 percent of those respondents. There is minimal use of face shields and/or goggles that come with helmets. How can I say that? During FDIC International, I paid particular attention to the videos of the H.O.T. training evolutions that occurred on the days before the general sessions. And, I studied the hundreds of photos that lined the walls in the long corridor between the Convention Center and the Lucas Oil Stadium. With several hundred examples, I found only one occurrence of helmet-provided eye protection being deployed. Almost without fail, firefighters had chosen to disregard the face shields, flip-downs, and goggles that come with helmets. In fact, a significant number of firefighters were wearing helmets without any eye/face protection. What were they using? Safety glasses. Safety glasses provide far superior protection over the ineffective protection provided with helmet-supplied face and eye protection. They are form fitting, may be sunglasses, and may have corrective lenses. NOTE: For structural firefighting, the self-contained breathing apparatus face piece, combined with a hood, provides excellent eye and face protection.

Are there better alternatives? Perhaps. Many fire departments have already adopted a policy of issuing two sets of turnout gear to its members. Other departments are aggressively seeking funding to do likewise. Typically, the second set consists of a turnout coat, turnout pants, a hood, and maybe a pair of gloves. Rarely is a second set of boots or a helmet issued. Since this topic is titled “From the Neck Up,” boots will not be discussed.

However, there might be a slightly different approach to issuing a second helmet. That approach is to offer only one structural helmet but then offer another multipurpose helmet. But first, why issue only one structural helmet? Because the need for a structural helmet for actual fire suppression is not nearly as high as the need for head, face, and eye protection for nonactive firefighting activities. One structural helmet should suffice if the helmet has a removable head band that could be easily cleaned or if each member were offered a second headband. Cleaning a helmet outershell is not that complicated and typically does not require any special equipment.

A Multipurpose Helmet

The thought of a multipurpose helmet occurred to me when I had a chance to participate in the Scottish Fire and Rescue Services Symposium in Glasgow this past May. The sponsors of the Symposium were allotted tabletop displays. One of the tables displayed a helmet that was designed for urban search and rescue (USAR), paramedic, and water rescue. The only nonstructural application it did not cover was wildland firefighting. Perhaps it could be redesigned or modified for wildland.

Read more

Posted: Sep 13, 2017

Understanding Fire Apparatus Brake Adjustment

By Chris Daly

Last month’s article addressed the issue of fire apparatus braking efficiency. Braking efficiency is the amount of available roadway friction a vehicle can put to use to skid to a stop. A vehicle with reduced braking efficiency will have a longer stopping distance.

In September 2016, a large-scale training exercise was conducted to evaluate the braking efficiency of fire apparatus. The results of this testing confirmed that fire apparatus have a reduced braking efficiency when compared to a passenger car. While most hydraulic-braked passenger vehicles have near 100 percent braking efficiency, the braking efficiency of a large fire apparatus averaged around 68 percent.

One of the interesting side effects of this testing exercise was a realization that many fire apparatus have improperly adjusted brakes. Of the 10 fire apparatus that arrived to participate, two were put out of service by law enforcement truck inspectors because of bad brakes. If a vehicle does not have properly adjusted air brakes, it will not be able to generate an effective braking force. As a result, the vehicle’s stopping distance could increase dramatically.

A comparison of stopping distances on a dry road based on skid tests conducted in September 2016. At each speed, the top vehicle represents the stopping distance of a passenger car. The middle vehicle represents the stopping distance of a fire apparatus with properly adjusted brakes. The bottom vehicle represents the stopping distance of a fire apparatus with brakes out of adjustment
A comparison of stopping distances on a dry road based on skid tests conducted in September 2016. At each speed, the top vehicle represents the stopping distance of a passenger car. The middle vehicle represents the stopping distance of a fire apparatus with properly adjusted brakes. The bottom vehicle represents the stopping distance of a fire apparatus with brakes out of adjustment.

These facts were made evident during the skid tests. Of the two apparatus that were found to have brakes out of adjustment, one also had a leaking airline. This truck was immediately placed out of service and was not available for testing. However, we were able to skid the other apparatus before and after the brakes were adjusted. This provided an invaluable opportunity to examine the difference in stopping distance between properly adjusted brakes and those out of adjustment. Needless to say, the results were startling.

On average, a fire apparatus with properly adjusted brakes had a 45 percent increase in stopping distance when compared to a passenger car. However, the apparatus with brakes out of adjustment had a 95 percent increase in stopping distance compared with a passenger car. The stopping distance of the fire apparatus with brakes out of adjustment was nearly twice that of a passenger vehicle. It is difficult enough to bring a moving fire apparatus to a safe stop. If brakes out of adjustment are added to the equation, they will significantly compound the problem.

How Air Brake Systems Work

To understand the importance of brake adjustment, it is important to discuss how an air brake system works. In summary:

  1. To apply the brakes, the driver presses down on the “foot valve,” otherwise known as the “brake pedal.”
  2. Air travels from the air tank reservoir through the air lines and into a brake chamber.
  3. Inside the brake chamber, the compressed air presses against a rub
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