Recently we have begun testing out pump cans. I like them better than water extinguishers because you can refill them on scene. I would support carrying only them and removing the water extinguisher altogether. We also carry dry chem and foam extinguishers on all first out engines.
I thought he meant back-pack sprayers. We use them a lot for grass fires. They work very good. We don't carry water extinguishers on our pumper. We've got the dry chemical and foam extinguishers and 4 backpacks. Put 4 guys in the grass/bush with them and they can put out a fire in a hurry. I'd have to double check, but I would guess that they hold about 4 gallons of water. No pressurization like a weed sprayer, just a pump-action wand.
(6) One approved dry chemical portable fire extinguisher with a minimum 80-B:C rating mounted in a bracket fastened to the apparatus
(7) One 21⁄2 gal (9.5 L) or larger water extinguisher mounted in a bracket fastened to the apparatus
I'm not sure the pump up sprayer qualifies as an "extinguisher". Several departments in my area carry them as a medium for the application of chemicals for fluid spills (ie topsol etc.)
While we are able to refill and recharge water cans on scene, we normally do not, preferring instead to fill them at the station where they can have the seal replaced.
We also carry the "native american cans," but this is a replacement for the water extinguisher as pictured below. Some might call them a hand pump extinguisher. We are using the 2.5 Gal to comply with 1901
All or Engine Companys cary back pack pumps for grass fires, and a pressurized water extinguisher. Our Ladder trucks cary a pressurized water extinguisher and a pump style like what Mike Batt pictured above.
All trucks cary the dry chem as required, and the engines also carry a Class D extinguisher.