Factoring Weight-Per-Firefighter When Choosing Handlines
By Skip Dorgan

Editor’s note: In an article in the February 2011 issue of FireRescue magazine (“Let the Pump Do the Work,” p. 62), Skip Dorgan provided the results of some comparisons between 1¾", 2" and 2½" hose, specifically comparing 2" vs. 2½" handlines noting that 2" hose can flow the same gpm with identical nozzle handling characteristic as the 2 ½” hose, but the weight of the handline is significantly less. In this complementary piece, Dorgan outlines another consideration when choosing various hoseline sizes for fire attack—how the weight of the hose with water flowing through it is distributed among the personnel operating the line.

Few fire departments these days, regardless of whether they’re career or volunteer, are staffed adequately for operations beyond routine incidents. What’s adequate is up for discussion, certainly, but it’s safe to say that very few departments are or will ever be staffed for the “big one.”

Staffing affects fire attack strategy in many ways, but in this article I’ll focus on just one: the weight of handlines. The heavier the handline, the more personnel needed to move it, and the fewer available for other fireground assignments. But we do have options when it comes to the weight of handlines.

Following are some results from calculations on hoseline weight. In an attempt to simulate realistic conditions, we’ll make the assumption that the firefighters will only be required to advance the last 100 feet of the hoseline; therefore, we’ll reference the weight of half of a 200' hoseline. .

By the Numbers

1¾" Line
A 200' length of charged 1 ¾" hoseline weighs approximately 288 lbs., so 100 feet (the length required for advancing the hose) weighs 144 lbs. Minimum staffing for that line would be two firefighters and the weight per firefighter would be 72 lbs. This is a typical scenario that most firefighters are familiar with and will be compared to the other scenarios.

• Equipped with a 100-psi operating pressure nozzle with a pump pressure of 150 psi, they would be flowing approximately 125 gpm or approximately 63 gpm for each firefighter.
• Equipped with a 15/16" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 185 gpm or approximately 92 gpm for each firefighter.

2" Line
A 200' length of charged 2" hoseline weighs approximately 360 lbs., so 100 feet (the length required for advancing the hose) weighs 180 lbs.

• Staffed by two firefighters, the weight per firefighter would be 90 lbs. each, approximately 25% more than the two firefighters on the 1 ¾" hoseline. With a 1 1/8" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 132.5 gpm each.
• Staffed by three firefighters, the weight per firefighter would be 60 lbs. each, approximately 20% less than the two firefighters on the 1¾" hoseline. With a 1 1/8" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 88 gpm each.
• Staffed by four firefighters, the weight per firefighter would be 45 lbs. each, approximately 37% less than the two firefighters on the 1¾" hoseline. With a 1 1/8" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 66 gpm each.
• Staffed by five firefighters, the weight per firefighter would be 36 lbs. each, approximately 50% less than the two firefighters on the 1 ¾” hoseline. With a 1 1/8” smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 53 gpm each.

2½" Line
A 200' length of charged 2½” hoseline weighs approximately 549 lbs., so 100 feet (the length required for advancing the hose) weighs 274 lbs.

• Staffed by three firefighters, the weight per firefighter would be 91.5 lbs each, approximately 27% more than the two firefighters on the 1¾" hoseline. With a 1 1/8" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 88 gpm each. Note: This is very similar the 2" hoseline with two firefighters flowing the same gpm with the same nozzle reaction.
• Staffed by four firefighters, the weight per firefighter would be 68.5 lbs each, approximately 5% less than the two firefighters on the 1¾" hoseline. With a 1 1/8" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 66 gpm each.
• Staffed by five firefighters, the weight per firefighter would be 55 lbs each, approximately 24% less than the two firefighters on the 1¾" hoseline. With a 1 1/8" smooth-bore tip at 50-psi nozzle pressure, they would be flowing approximately 265 gpm or 53 gpm each.

Now let’s look specifically at a comparison between the operation of a 2" handline with that of a 2½". Both handlines will be equipped with a 1 1/8" smooth-bore tip flowing 265 gpm.

• 200 feet of 2½" hose pumped at 80 psi with a 1 1/8" smooth-bore tip at 50-psi nozzle pressure will flow 265 gpm with 99 lbs. of nozzle reaction. Friction loss is 15 psi per 100 feet of hose.
• 200 feet of 2" hose pumped at 165 psi with a 1 1/8" smooth-bore tip at 50-psi nozzle pressure will flow 265 gpm with 99 lbs nozzle reaction. Friction loss is 60 psi per 100 feet of hose.

Conclusion
Although the flow and nozzle reaction associated with both hoselines is the same, the physical weight of the 2½" hoseline is 33% heavier than that of the 2" hoseline. Assuming we have three firefighters to stretch each of these hoselines, the weight-per-firefighter for the 2½" hoseline is 91.5 lbs., compared to 60 lbs. for the 2" hoseline. This makes the 2½" hoseline 52% heavier per firefighter than the 2"hoseline.  

Again using the 1¾" handline staffed by two firefighters for comparison, at 72 lbs. per firefighter, the 2" handline staffed by three firefighters would have a weight-per-firefighter approximately 20% less than the 1¾" handline, while the weight-per-firefighter of the 2½" handline staffed by three firefighters would be more than 25% heavier than the 1¾" handline. The required pump pressure to flow 265 gpm is 80 psi for the 2½" hose line and 165 psi for the 2" handline.

My recommendation: Pump the hoseline at the higher pressure and let the pump do the work, rather than the firefighters. Another side benefit from the pump operator’s perspective: The 1¾" and 2" handlines would be pumped at pressures that are relatively close together, making the pump operator’s job a little easier.

Before changing any of your tactics, conduct actual water flow evolutions with the hose your department has to see if the data comes out the same. Different hose has varying flow characteristics, depending on the brand, manufacturer and age.

Skip Dorgan has served 33 years in the fire service, including 27 years as a career firefighter with the Kodak Fire Department in Rochester, N.Y., where he’s presently a battalion chief. Previously, he was chief of a volunteer fire department. Dorgan holds an associate’s degree in fire protection technology, is a nationally certified NFPA Level II Fire Instructor and Level II Fire Officer, and a New York State Fire Instructor.


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