Handwarmer expire dates.

robby denning

Administrator
Staff member
Joined
Feb 25, 2012
Messages
15,726
Location
SE Idaho
I’d hesitated to even take them on hunts when they were expired.

I found some in my drawer that were 10+ years old.
4b8ca0e4475c8b9c516d207fd10f47be.jpg



abbe7df02cfed6c233b67120f96594b2.jpg


I went for a horse ride Saturday so I gave them a shot.

Worked fine for 2 1/2 hours, still warm when sealed them up in a snack bag, cut off the oxygen and probably be able to use one more time.

Anybody else go way past expiration dates on these? What was your experience?


Sent from my iPhone using Tapatalk
 
Joined
Apr 5, 2015
Messages
5,944
I have, but I will tend to rotate the older ones to uses that aren’t as high stakes as backcountry use. I finally used up an off brand box that expired in 2015. I think they are probably OK as long as the packaging is in decent shape. The ones that were duds were obvious - hard as a rock.

TBH at $6-7 a bag, I treat myself to a new bag for late season hunts Or situations when them not working would be a serious issue.
 
Joined
Jan 13, 2015
Messages
849
Location
Veradale, Wa
I bought a costco box a few years ago and am just about to the bottom of it. Mine don't work for shit now, but I think it's because I kept them out in the garage. Maybe they keep better being out of the freezing temps.
 
OP
robby denning

robby denning

Administrator
Staff member
Joined
Feb 25, 2012
Messages
15,726
Location
SE Idaho
I have, but I will tend to rotate the older ones to uses that aren’t as high stakes as backcountry use.
only on Rokslide is this stuff high stakes lol. That’s exactly why I was throwing away the ones that were expired. Thanks for your feedback.
 
OP
robby denning

robby denning

Administrator
Staff member
Joined
Feb 25, 2012
Messages
15,726
Location
SE Idaho
I bought a costco box a few years ago and am just about to the bottom of it. Mine don't work for shit now, but I think it's because I kept them out in the garage. Maybe they keep better being out of the freezing temps.
Not sure.

Any chemists on here know what the reaction is causing the heat and what affects it?
 

manitou1

WKR
Joined
Mar 29, 2017
Messages
1,936
Location
Wyoming
They seldom make it to the next season for us. They just don't work after they have sat a while.
I found a whole case of them while looking for items in the basement last week. They are several years old, so I doubt they will heat up.
 
Joined
Apr 8, 2019
Messages
1,975
Didn't know they have expiration dates...I just always chuck the rock hard ones and use the rest...probably why some work better than others...

If its cold I just use my zippo.
 
Joined
Feb 1, 2021
Messages
84
Location
Upper Michigan
I find that their performance varies with brand, I’ve had some like the ones you used still work way after the exp date. Other brands no good the next year, not sure if storage conditions matter but makes sense.
 
Joined
Apr 5, 2015
Messages
5,944
Not sure.

Any chemists on here know what the reaction is causing the heat and what affects it?
It’s an iron compound that oxidizes. Exposure to air starts it and cutting off air can slow it down or even stop it but it is a finite process. Once all the iron reacts, they are done. Pin holes in the wrapper will start the process. Those rock hard ones are fully oxidized due to faulty or compromised packaging. I imagine the packing and glue degrades over time and that’s probably why they expire.
 
Joined
Jul 30, 2019
Messages
845
I always buy a 2 pack case of 240 total. Use them until they are gone and then reorder. I have never worried about an expiration date. Never had a problem or a failure. These are for the larger 18 hour ones. I don’t buy the smaller shorter duration ones.
 
Last edited:

hiker270

WKR
Joined
Nov 5, 2022
Messages
534
I have used them 2 years after expiration date and they worked fine. Don't know about 10.
 

rclouse79

WKR
Joined
Dec 10, 2019
Messages
1,884
I have some ones from years past. Every once in a while I get a dud, but most of them seem to work.
 
OP
robby denning

robby denning

Administrator
Staff member
Joined
Feb 25, 2012
Messages
15,726
Location
SE Idaho
It’s an iron compound that oxidizes. Exposure to air starts it and cutting off air can slow it down or even stop it but it is a finite process. Once all the iron reacts, they are done. Pin holes in the wrapper will start the process. Those rock hard ones are fully oxidized due to faulty or compromised packaging. I imagine the packing and glue degrades over time and that’s probably why they expire.
I knew there was a WKR out there with the intel.

Thanks for the clarification

So, as long as they’re still soft, I’m gonna use them
 

thedutchtouch

Lil-Rokslider
Joined
Sep 2, 2021
Messages
186
While we are talking hand warmers, the hand and foot and body warmers are all basically the same stuff, the thing that makes them different is the porosity of the packaging. Toe warmers are more porous since they are designed to be inside a shoe in an Oxygen depleted environment so have a more porous bag than the hand warmers. Same reason shaking the hand warmer can get it going again, you're exposing more of the iron to oxygen.

Strange that oxidized iron can help like this but be a real pain in the form we are more used to (rust)
 

rclouse79

WKR
Joined
Dec 10, 2019
Messages
1,884
I noticed that when you put the foot warmers in a pair of rubber winter boots, they don't get enough oxygen to fire up. When you take them out at the end of the day the get hot.
 

Ens Entium

Lil-Rokslider
Joined
Mar 4, 2016
Messages
157
Location
So Cal
It’s an iron compound that oxidizes. Exposure to air starts it and cutting off air can slow it down or even stop it but it is a finite process. Once all the iron reacts, they are done. Pin holes in the wrapper will start the process. Those rock hard ones are fully oxidized due to faulty or compromised packaging. I imagine the packing and glue degrades over time and that’s probably why they expire.
To add to this expiration dates tend to be there to remove liability from a manufacturer rather than guide the consumer when to use their product.
 
Joined
Apr 5, 2015
Messages
5,944
To add to this expiration dates tend to be there to remove liability from a manufacturer rather than guide the consumer when to use their product.
Don’t disagree.

I think there are an awful lot of products with bullshit expiration dates that don’t really add any value for the consumer. for a few things, I will abide by them. I use expired hand warmers on the regular for a lot of things, but I carry a few as part of my “aw shit“ plan in addition to using them as comfort items. Lighting fires or anything that requires fine motor skills with frozen hands is no bueno IMO, so I keep a few hand warmers in my “emergency” gear. I also Prefer to get fresh ones for trips that are cold and deep in the woods where cold hands would be a real issue. Closer to the house/truck or whatever, I use what I have.
 

Latest posts

Featured Video

Stats

Threads
349,770
Messages
3,684,892
Members
80,002
Latest member
Mira
Top