LETTERS TO THE EDITOR

LETTERS TO THE EDITOR

Ammunition fires—uncertainties and additional considerations

The November 1984 issue’s article “Ammunition Fires—Shooting Away Misconceptions” interested me. From time to time, other articles in other magazines have indicated that there is no really serious danger posed by fires involving ammunition.

I know that anecdotal evidence does not have the standing of more formal testing based evidence, yet I feel the need to share one anecdote from the dim and distant past.

In the early 1960s, I was a member of the Phoenix, AZ, Fire Department. I responded to the scene of a working fire in a shop that sold guns and ammunition. Contrary to your article and to most other pieces that I have read on ammunition fires indicating that projectile hazards are minimal, some cars at both the fireside curb and the curb across the four-lane urban street had projectile-caused dents and holes punched in their fire exposed sides. The ground was littered with shell casings. The front plate glass windows were out, but they apparently had been out and fire blowing through when the first companies arrived.

This is just one fire, of course, and I have no way of drawing generalizations. Fire attacks in those days were, initially at least, often made with 2 1/2inch hose streams at direct hydrant pressures. Most of us were then fighting daytime fires in short canvas coats, fiberglass helmets, black jeans, and street shoes.

Richard L. Ulrich Associate Professor Montgomery College Rockville, MD

The article in the November 1984 issue of FIRE ENGINEERING entitled “Ammunition Fires—Shooting Away Misconceptions” was very interesting, but possibly misleading because it did not mention the other dangers associated with ammunition fires.

Several years ago, our department responded to a house fire that involved ammunition exploding. Sure enough, exploded shells were on the floor near a gun rack. However, as it turned out, the real danger was a lever action rifle with a tube type magazine under the barrel. Apparently, a shell went off in the magazine sending the magazine through the top of the wooden gun rack. What would have been the consequences if the rifle was in another position and firefighters were in the wrong place? Can a shell “cook-off” in the chamber? How many homes and businesses have loaded weapons lying around?

A more recent situation involving a sporting goods store in Roswell, GA, brings to mind the potential danger of bulk powder. An explosion was supposedly touched off by kegs of powder overheating. If this is true, bulk powder may be more of a problem than ammunition.

A. W. Delay

Assistant Chief

Hickory Flat Fire Department

Canton, GA

FIRE ENGINEERING’S 1984 Index

Due to a shortage of space and an abundance of valuable material, our index for last year could not be printed in the pages of FIRE ENGINEERING.

However, anyone wishing a copy of our 1984 listing of articles and authors can have one free of charge by writing to:

FIRE ENGINEERING

875 Third Avenue

New York, NY 10022

Thanks again for a great year.

Tom Brennan

Editor

Keep the basics in mind

I think the changes initiated at FIRE ENGINEERING have made the magazine more informative and enjoyable, and the articles can only improve our profession.

The article on forcible entry (May 1984) was extremely valuable and I believe that an article written along those lines, addressing a different firefighting function, should be printed every month. In reality, that article did not only touch the basics (I can get the basics out of a training manual) but included some veiy valuable “tricks of the trade” that reflect the experience of its authors.

You have many readers, perhaps a majority, who will never select the computer software for their department or command a fire scene, but who are involved in handling ladders, forcing doors, and stretching hose on an all too frequent basis.

William Gustin

Lieutenant

Metro-Dade County Fire Department

Miami, FL

Fire flow affected by appliances

I enjoyed the article in the September 1984 issue of FIRE ENGINEERING relating to matrixing for fire flow (“Model Incident Command System Series: Resource Capability”). Our department also has taken this approach to estimating capabilities. We ran into one problem that is, I dare say, a variable in most departments’ experience: that the fire flow estimate in gpm does not conform to the actual flow rate of the appliances being used.

The article indicates gpm flow rates for specific sized handlines. In flow testing all the nozzles in our department, I found few nozzles that could be depended on to deliver the prescribed amounts. The nozzles for 2 1/2-inch lines, for example, delivered anywhere from 120 gpm to 325 gpm. Most of our appliances deliver lower gpms.

In order to move towards a more accurate figure for interior or offensive attack appliance flow rates, we tested the flow on all appliances and published a list of the findings. Each company can now matrix their capability and recognize the actual flow rate for each situation. This then becomes a basis for pre-fire planning for each apparatus. An average flow rate for a given alarm response can be calculated for battalion chiefs so that capabilities of resources are more accurate.

To give you an idea of what our findings revealed, a nozzle with gpm flow settings of 120, 150, 200, and 250 gpm actually developed 90, 120, 150, and 175 gpm respectively when tested. These tests were conducted at standard department policy nozzle pressures which are lower than those the manufacturer uses to set flow standards.

As you can see, if a matrix of 500 gpm is established using potential flow based on hose size, the actual flow will be only 70% of the estimated flow with this nozzle. That is to say, if the matrix shows that two 2 1/2-inch lines can be used and a 2½-inch line produces 250 gpm, then using the nozzle above set for 250 gpm on a 2 1/2-inch line will produce only 350 gpm for two lines.

The idea of applying approximate gpm flow rates to a given number of personnel is a good way of applying resources to the task at hand. We must be careful not to use too many suppositions for fear of creating a false sense of our true abilities.

Richard D. Wattenbarger Battalion Chief / Director of Training

Michael L. Burtch

Captain/Training Officer

San Jose, CA, Fire Department

El Paso fire

Large Fire Erupts Near El Paso (TX) International Airport, Injuring Five

A fire broke out at a transportation center next to the international airport in El Paso, Texas, on Tuesday.

East Haven (CT) Fire Engine Struck in a Hit-and-Run

An East Haven Fire Department engine was struck in a hit-and-run Tuesday evening while it was driving to a structure fire in the Foxon area.