Ask at your local fire station, ours takes the non-serviceable kind and puts them to work doing PASS demonstrations. Not sure what they do with them afterwards, but they accept them.

a couple of years ago (gad it's that long already?) a friend in the fire protection business looked at me and said "want some fire extinguishers?" It seems at one of his sites, someone had magic markered on 3 units, and because of this, they either needed a repaint, or replace to pass in a commercial building - so I got 3 nice 20 lb units - one of which I gave away

Lets see - 1 5lb in the kitchen, a 20lb upstairs - hall closet next to steps, one 1st floor, next to fireplace, but closer to the door, 2 units down the basement (a dry powder and a CO2), and a pair in the garage - I guess I'm well covered - or at least better than MOST, although not quite as crazy as my friend upstate - he had a hydrant put in, and had a pumper (used) in the garage - of course he had been the local chief, and he and his son had more than a clue how to use the gear

How do fire extinguishers compare to other tools, eg a fire blanket or a bucket of sand?

It is going to depend on your application. All in all, the appropriate size and type of extinguisher are better for most applications then either a sand bucket or fire blanket.

Now, if you are working with metals in your garage a bucket of sand would be a GREAT idea to have around.

The best thing for an incipent grease fire contained in a pot or frying pan is to just put a lid on it.

I saw one of those new aerosol can extinguishers on sale at the hardware store so I bought it. I showed it to my wife and told her I figured it would be more intuitive for her to use that the dry chem in case of a grease fire. She replied "Why do you think I keep a throw rug in front of the stove?" Smart lady.

Not sute what you exsacly mean with a aerosol can extinguisher but if a pan full of oil is on fire, than either put the lid on, a fire blanket or use a special grease extinguisher. A aerosol can doe'sn't sound like any of them...

hereyougo:
http://www.firstalert.com/tundra_fire_extinguishing_spray.php

Replying to myself here... The MSDS I found shows a basic pH and Potassium Hydroxide as an ingredient.

This should be excellent for grease fires. H20+KOH+hot oil=Soap

I worked a summer internship for a fire protection company doing R&D and UL qualifications of wet chemical systems for commercial kitchens. Unlike dry chem, the aqueous solution helps cool the oil by evaporation and forms a soap layer the floats on the surface of the oil.

Once, when the system under test failed, I manually put out a 36" wok filled to the brim with 600 degree flaming oil with a 2-1/2 gal "A" type extinguisher that was charged with this solution.

************ DO NOT USE PLAIN WATER ON A GREASE FIRE *****************

I was randomly researching Tundra, too, and the MSDS I stumbled across listed potassium lactate as the main fire fighting ingredient but no mention of KOH. I thought potassium lactate sounded familiar...looked it up and it is also a common food preservative. Well, anyone who is wondering if it's toxic--they've probably been eating it for a long time already.

Anyway, apparently Tundra is not approved for sale in California, so I guess that I won't be seeing it sold in stores here.

One interesting thing about Tundra is that the solution is kept in a sealed bag inside the can, separate from the propellant. When you press the nozzle down, I guess the tube punctures the bag and pressurizes the solution. I don't believe that the small Fireade2000 extinguisher I just got uses that system.

I would be nervous as heck standing in front of a restaurant-size wok full of flaming oil no matter what kind of extinguisher I had in my hands!

Target Fixation.

I had bunker gear but I forgot to put on gloves and singed the hair off my knuckles. On the video you could hear the other guys yelling "BACK UP!" but I didn't hear them.