2297: Use or Discard By

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Use or Discard By
One of the things of bear spray says that, and I'm not one to disobey safety instructions, but there are no bears around here. Guess it's time for a camping trip where we leave lots of food out!
Title text: One of the things of bear spray says that, and I'm not one to disobey safety instructions, but there are no bears around here. Guess it's time for a camping trip where we leave lots of food out!


Many products carry a "Use By", "Expiration date", "Discard by" or similar date. The date shows the latest date by which the product has been verified to provide its expected use. For example, a foodstuff will have a "consume by" date, showing the date after which the food may be unsuitable for eating. In most cases, this will be a conservative estimate, and the useful lifetime can be significantly extended by proper storage.

One of the issues around expiration dates is that the language used is decided on by the manufacturer, making them highly variable and often ambiguous. Some have explicit instructions to the consumer, such as "use by:", others have instructions to the seller, such as "sell by:", still others say things such as "best by:" or "freshest before:". This can make it confusing how important it is to avoid using a product past a given date.

For many consumer goods, the expiration dates are of minimal importance, and using them afterward risks nothing more than a drop in quality. In certain cases, however, they can have safety implications. Some foods, if kept too long, become dangerous to consume. Medications can lose their potency over time, and relying on them past the expiration date could put a person's health at risk.

In this comic, two similar emergency flare guns, an item typically used to send out distress flares, have slightly different expiry instructions. One has an instruction to "use by or discard by" a specific date (in this case, three days after the date of publishing). The other has an instruction to "use by" this date. These two phrases almost certainly have the same intent. The older flares are, the less reliable they become, so the manufacturer recommends regularly replacing unused flares with working ones, to ensure that working flares are available in case of an emergency.

Megan, however, seems to take the latter instruction literally, as an order to actually fire the flare gun prior to the expiration date, whether or not it's necessary. It may be taken that she wants the experience of firing a flare, and takes that instruction as an excuse to do so. Cueball immediately objects to this line of reasoning. Firing a flare unnecessarily is generally a bad idea. It could summon emergency responders to a non-emergency situation, diverting emergency resources that may be needed elsewhere. Even worse, if a flare is fired improperly, or in an unsafe direction, it could cause a fire and/or injuries, ironically creating an emergency situation, rather than signaling one.

The title text similarly indicates that Megan encountered similar instructions on a can of bear spray. Since there are no bears present, she intends go camping and leave her food out to attract bears, so that she may use the bear spray to repel them before it "goes bad". Clearly, this would be a bad idea. While bear spray is a useful emergency measure, there are many reasons why it could fail to protect the user, which would risk severe injury or death. Even if the bear spray effectively protected Megan, deliberately baiting wildlife so that you can repel them with a painful irritant would be irresponsible and cruel. In both cases, the humor derives from the language that appears to instruct the use of an emergency product, even if no emergency has occurred. In both cases, taking such instructions literally would risk causing injuries, rather than preventing them.

Expiration dates (for food) have also been mentioned in 737: Yogurt, 1109: Refrigerator, and 2178: Expiration Date High Score.


[Megan stands in the middle of the panel, holding two flare guns, one in each hand.]
Megan: These emergency flare guns are about to expire.
Cueball [off-panel]: I forgot we had those.
[Cueball sitting at a desk, working on a computer.]
Megan [off-panel]: This one says "Use or discard by Apr 25 2020."
Cueball: Okay...
[Megan holds up one of the flare guns looking at it. She holds the other flare gun by her side.]
Megan: But this one just says "Use by" ...
Cueball [off-panel]: No.


  • Twenty-seven years ago exactly (April 22, 1993), Calvin and Hobbes made a similar joke about expiration dates on milk. Obviously the humor has a very long shelf-life.
  • This comic shares some similarities with 1821: Incinerator, particularly in the last panel.

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comics featuring expiration dates

This comic is definitely not related to the COVID-19 theme. Has Randall decided after 19 (or 20) comics to end his series? 01:28, 23 April 2020 (UTC)

I personally agree. However some will make the argument that all the people who stocked up on a lifetime supply will face "best by" issues in the next years. -- 06:29, 23 April 2020 (UTC)
This one is satisfactorily unrelated for me. I was for Exa-Exabyte, and although I understand the slight argument someone had for it, against Garbage. But this one surely only has convoluted arguments on par with the symbiotic relationship it has with yeast. 12:40, 23 April 2020 (UTC)
This one feels like a "things to do while stuck at home" that may have been inspired by the COVID-19 lockdown, but that doesn't make it a COVID-related comic. --Bobson (talk) 14:06, 23 April 2020 (UTC)
This is clearly referencing CoViD-19 preppers 23:26, 26 April 2020 (UTC)

She didn’t say it said “use by (some date)”. She just said it says “use by ..”. My interpretation is that it is so old the date has worn off. That happens to my nitroglycerin quite often. I think her interlocutor is saying, if the date has worn off or gotten illegibly smeared, assume it’s expired. —— OTOH the explanation given by the editors is funnier! 05:08, 23 April 2020 (UTC)

In the first panel she states that the guns (plural) are about to expire. So I guess they have bought 2 guns about the same time, from different vendors who handle this wording differently, but both flare guns have a visible expiry date in the close future. --Lupo (talk) 05:56, 23 April 2020 (UTC)
I disagree. The other one says Use By and no date. So think either explanation is wrong, or at least the two possible interpretations should be mentioned --Kynde (talk) 14:56, 23 April 2020 (UTC)

I'm struggling to imagine how anyone could come up with such a wrong interpretation. It's dead obvious, at least to a native English-speaker, that the second label reads in full 'Use by April 25 , 2020" and that it's the missing "or discard" that makes the joke. Cellocgw (talk) 13:56, 24 April 2020 (UTC)

My interpretation of that panel is that Cueball cut her off before she was able to finish her sentence, aware that she was interested in using the flare gun. 17:24, 23 April 2020 (UTC)
If she would have been unable to read the date, how would you explain that she knows the gun is "about to expire"? Especially if they were from different manufacturers, there's no way to know when the gun expires, apart from reading the date. 18:44, 23 April 2020 (UTC)

I play the browser-game Urban Dead. The flare-pistols in that have no expiry date (a handy 15HP damage item, if they hit, so I often save any I scavenge for a time my Action Points are low but I might appreciate a chance killing shot on a worn-down zombie) and are 'safe' to fire at all times - except for your target if hit, of course. Outside they can act as a signal, though never seen that as useful myself, but I always wished that inside a darkened building they'd at least be seen as a flash (maybe transient blinding) to anyone present but not hit by it. I mean, does nobody notice someone firing off a flare in an unpowered cinema, even the person it was aimed at but apparently just missed? (It was argued that a 'miss' was a misfire, a similar argument given with shotgun/pistol non-hits that no-one even hears, but they have no failure rate when deployed as signal.) 13:46, 23 April 2020 (UTC)

How does one properly dispose of these? I have an emergency smoke"grenade" (it's just a tin can) that expired in or before 2012 in my car. Related question, what is the best way to improperly dispose one of those? 15:39, 23 April 2020 (UTC)

Probably need to contact your local HAZMAT for either smoke grenades or flare guns. Neither one would be appropriate for regular garbage or recycling. And forget about taking them on an airplane. Rtanenbaum (talk) 16:55, 23 April 2020 (UTC)

Here is an article from the American Boating Association about what to do with old flares. Two take aways: 1. keep the older flares (3 years old) as backups, but use them first in an emergency to save the more recent ones. 2. contact your local fire department or sanitation department for disposal. https://americanboating.org/flares.asp Rtanenbaum (talk) 19:50, 24 April 2020 (UTC)