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Firefighter Math

firefightermath.org

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Re: Firefighter Math

#11

Post by ateesdalejr »

knz wrote: post #9
johansch wrote: post #6

http://www.firefightermath.org/index.php?option=com_content&... "A 100-foot length of 1-inch diameter hose is charged with water. How many gallons of water are in that length of hose?" Ugh.

The section on unit conversions ( http://www.firefightermath.org/index.php?option=com_content&... ) just makes me wonder why fire fighters don't use metric... "How many pints are in a 5-gallon pail? How many cups are in a 5-gallon pail?"

Probably because most firefighters were taught and grown up on the imperial system of measurement...

Re: Firefighter Math

#12

Post by firethief »

johansch wrote: post #6

http://www.firefightermath.org/index.php?option=com_content&... "A 100-foot length of 1-inch diameter hose is charged with water. How many gallons of water are in that length of hose?" Ugh.

It's not that bad if you don't need an exact answer. Just convert to metric, multiply it out, and convert back.

Re: Firefighter Math

#13

Post by johansch »

firethief wrote: post #12
johansch wrote: post #6

http://www.firefightermath.org/index.php?option=com_content&... "A 100-foot length of 1-inch diameter hose is charged with water. How many gallons of water are in that length of hose?" Ugh.

It's not that bad if you don't need an exact answer. Just convert to metric, multiply it out, and convert back.

That is.. bad, particularly since the presumed context here is about fire emergencies where speed is of the essence. Any extra steps will add delays and/or opportunities for potentially disastrous mistakes.

https://motherboard.vice.com/en_us/article/qkvzb5/the-time-n...

Re: Firefighter Math

#15

Post by brooksgarrett »

knz wrote: post #9
johansch wrote: post #6

http://www.firefightermath.org/index.php?option=com_content&... "A 100-foot length of 1-inch diameter hose is charged with water. How many gallons of water are in that length of hose?" Ugh.

The section on unit conversions ( http://www.firefightermath.org/index.php?option=com_content&... ) just makes me wonder why fire fighters don't use metric... "How many pints are in a 5-gallon pail? How many cups are in a 5-gallon pail?"

Speaking from experience, it's primarily due to 'tradition.' All of your combi-nozzles and rate control valves are rated and marked in GPM (Gallons per minute) and hose is purchased and stored as 50' sections. NFPA specifications for the hose required on a first due engine are in feet.

A department can't decide to use metric alone. The entire industry first would need to support at the minimum both standards.

Re: Firefighter Math

#16

Post by brooksgarrett »

junkscience2017 wrote: post #4
taxicabjesus wrote: post #2

After I 'retired' from taxi-driving, the volunteer fire department for my grandfather's (deceased) rural cabin sent a bunch of us to the Arizona State Fire School [0]. This organization provides training for small fire departments that don't have the resources to run their own training. Topics covered include basic firefighting, how to drive a firetruck, fire investigation (arson?), etc. [0] https://www.facebook.com/…

It would seem that assisting at auto accident scenes now constitute 95% of actual calls firefighters make (i.e. discounting false-alarm calls)...which makes me wonder why there isn't an effort to situate fire stations right on major highways. Where I live in California there has been only one house fire in our town in years, but the fire department is on the highway responding to an accident at least once a week.

If you have fire based EMS then that will account for the vast majority of your call volume, full stop. Accidents requiring extrication are rapidly decreasing as cars are becoming safer. Additionally, homes are becoming drastically less at risk of fire (to the point many municipalities now include residential suppression sprinkler systems as a building code requirement.)

As an anectdote, my district has around 10 miles of interstate and 20 miles of major highways. Our call volume is, in order of prevalence,: 1. Fire Alarm (Only 2 have ever been actual 'fires') 2. Medical Assistance (We are EMR, not EMS) 3. Grass fires / Trash fires 4. Accidents 5. Building fires 6. Something else

Our neighboring district has a ton of farms and little to no major roads. They may receive a total of 20 calls per year compared with over 300 in our station. (Both low volumes but the type of response is reflected.)

Re: Firefighter Math

#17

Post by johansch »

brooksgarrett wrote: post #15
knz wrote: post #9

Earlier quoted context omitted.

The section on unit conversions ( http://www.firefightermath.org/index.php?option=com_content&... ) just makes me wonder why fire fighters don't use metric... "How many pints are in a 5-gallon pail? How many cups are in a 5-gallon pail?"

Speaking from experience, it's primarily due to 'tradition.' All of your combi-nozzles and rate control valves are rated and marked in GPM (Gallons per minute) and hose is purchased and stored as 50' sections. NFPA specifications for the hose required on a first due engine are in feet. A department can't decide to use metric alone. The entire industry first would need to support at the minimum both standards.

It's probably possible, somehow, to quantify how many americans perish every year because of this.

Re: Firefighter Math

#18

Post by marcosdumay »

taxicabjesus wrote: post #2

After I 'retired' from taxi-driving, the volunteer fire department for my grandfather's (deceased) rural cabin sent a bunch of us to the Arizona State Fire School [0]. This organization provides training for small fire departments that don't have the resources to run their own training. Topics covered include basic firefighting, how to drive a firetruck, fire investigation (arson?), etc. [0] https://www.facebook.com/…

> I don't know why the president of our volunteer fire department decided 3 of us needed to learn about Vehicle Extrication

Maybe because when you need it, you need it instantly, so he wanted to always have somebody with that knowledge on the current turn?

Re: Firefighter Math

#19

Post by Scoundreller »

johansch wrote: post #13
firethief wrote: post #12

Earlier quoted context omitted.

It's not that bad if you don't need an exact answer. Just convert to metric, multiply it out, and convert back.

That is.. bad, particularly since the presumed context here is about fire emergencies where speed is of the essence. Any extra steps will add delays and/or opportunities for potentially disastrous mistakes. https://motherboard.vice.com/en_us/article/qkvzb5/the-time-n...

It’s not as bad as you make it sound.

The original problem requires plenty of conversions (to cubic inches) and memorization of infrequently used constants (how many cubic inches in a gallon?).

If imperial isn’t your thing, doing it in metric is easier, at least it was for me.

Re: Firefighter Math

#20

Post by jcranmer »

johansch wrote: post #6

http://www.firefightermath.org/index.php?option=com_content&... "A 100-foot length of 1-inch diameter hose is charged with water. How many gallons of water are in that length of hose?" Ugh.

"A 100m length of 1cm hose is charged with water. How many liters (1 dm³) of water are in that length of hose?"

That problem is still no fun to do in your head. If it's important to do frequently, it's not hard to memorize the constant for "1 ft of 1 in-diameter hose = X gallons" and then multiply as appropriate.

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