FAQ: How gas mask filters work, finally understood.

[Proph]

I have posted this as a guide. Here is the link. is http://steamcommunity.com/sharedfiles/filedetails/?id=141095645#47896

Since google searches for how the filters actually work in the game have come up with many varied responses, some of them contradictory, I thought I'd share the known facts here.

How much time is on a filter?

It varies, a random filter found in the game world will usually have about one minute of air time, whereas a filter bought from a merchant will have 10 minutes of air time. The time you have remaining on a filter is unaffected by your actions (running or jumping), but it is theorized that if Artyom is at "rest" (not breathing heavily, or even better standing near a fire to "calm" him) you will get more time on the filter when you swap one in. That is unconfirmed though, and doesn't seem to affect your total time available. It is important to note though that if your gas mask becomes cracked, your filter will get used up faster (unconfirmed).

How do I know how many filters I have remaining?

This information is not shown to you, and it seems to be irrelevant because you don't actually run out of filters, you run out of breathing time.

How do I read Artyom's watch?

The red hand which moves counter-clockwise will be either in the green, yellow, or red areas of the watch. It is a countdown timer that shows how many minutes of air time you have remaining on the filter that you are wearing (e.g. if it's in the yellow you have less than 10 minutes, red less than 5, and when it reaches zero Artyom automatically changes his filter).

Help! My watch is broken, it always says I only have one minute left on my filter!

Some people say that their watch is "broken" and never moves out of the red, this is probably because you're out of "good" filters and have to keep using filters that only have one or two minutes of air. If you buy a filter you'll see that the watch works, but since you can only buy filters at Riga or Market you're probably going to be stuck with bum filters for the rest of the game.

What is the number next to the gas mask icon? I've been told it's how much air is left on the filter.

Not quite. Artyom's watch is the only measure of how much time is on a filter, what the number below the gas mask icon shows is how much TOTAL filter time you have among all your filters. If it says 10 you have 10 minutes of air, and it can be with 10 filters that have only one minute left, or 1 filter with 10 minutes.

Is there a maximum amount of filtered breathing time you can have?

Yes, no matter how many filters you buy you can't get the amount of time you have remaining over the ~40 minute range. The reason it is not a set number is because if you buy a filter that puts you over 40 minutes you then can't buy another one, e.g. if you were at 31 minutes and bought a filter it would put you at 41, but buying another wouldn't put you at a max it just would expend the money and you would not get a filter. I theorize that the max possible you can get is 49, but I haven't been able to test this.

Why can I pick up filters some times but not all the time?

This is not something that is entirely clear. It is possible that there is a maximum amount of filters you can carry, but there is no way to know. What it seems though is that if you have a certain amount of time left total on your filters, then it won't let you pick up new filters (I usually need to have under 25 minutes of time left before it will let me pick up filters found outside).

Why do the filters I find only last one minute, but the ones I buy last 10?

It's either for gameplay challenge reasons, or realism. At the time the game takes place all the filters should be expired. It's possible that the crappy filters you find are meant to be used or expired, whereas the ones you buy are recently made. Gas mask filters are somtimes made with charcoal, so it's not unrealistic to assume that it is within the Metro citizen's capabilities to create new gas mask filters.

Where can I buy filters? None of the merchants sell them!

Only the merchants at Riga station and Market station sell filters. It's not known why, but it is certainly a frustration as you can't get new filters later in the game. Stock up early if you can. Note though that even the merchants who don't sell filters will still hawk, "Medkits! Filters! Knives!" since the sound file is not specific to the merchants.

Hope this helps some people.

[1BreathTaken]

Figured out how to fix the issue with a glitched gas mask (cracked/broken and no air filters so you can't take it off or replace it).

Get a hex editor, and edit your save file. you'll have to copy+paste exact area's until you've matched the correct lines that replace the gasmask. I find anything after <player.config and before attack_0 work well. As well as the code around low before gasmask_off or similar.

if you know anything about hex editting, it'll be a breeze. Otherwise, youre better off just grabbing an earlier save/checkpoint.

[lk]

I'm sure it's been mentioned at some point. There is a button that the player can use to manually switch filters, though I've never understood why it is there. Artyom will automatically swap filters when he needs to. Unlike last light, where the player actually has to swap filters themselves.

[jpblazaro]

Hi guys, I was wondering if anybody would be able to help me figure this out... I'm having a massive problems with the filters because I simply cannot pick them up. Not a single one of them.

I stocked up at Riga and at Market, had like 40 minutes worth of air... But every time, every single time I find a filter lying around somewhere, no matter how much I smack the E key to pick it up, nothing happens.

This didn't happen the first time I played the game. But then I died coming out of Polis because I ran out of air and had to start over.

Reading this topic made me think there might have been a glitch at Riga or something like that, when I tried buying as many filters as I could and then it went over the 40 minute mark (I did note that it was pointless to try and buy any more!), but then I wonder if this makes it impossible to pick up any filters later on, because I just don't understand why this is happening...

[Jig McGalliger]

jpblazaro님이 먼저 게시:

Hi guys, I was wondering if anybody would be able to help me figure this out... I'm having a massive problems with the filters because I simply cannot pick them up. Not a single one of them.

I stocked up at Riga and at Market, had like 40 minutes worth of air... But every time, every single time I find a filter lying around somewhere, no matter how much I smack the E key to pick it up, nothing happens.

This didn't happen the first time I played the game. But then I died coming out of Polis because I ran out of air and had to start over.

Reading this topic made me think there might have been a glitch at Riga or something like that, when I tried buying as many filters as I could and then it went over the 40 minute mark (I did note that it was pointless to try and buy any more!), but then I wonder if this makes it impossible to pick up any filters later on, because I just don't understand why this is happening...

There is a max amount of filter time one can hold.

[jpblazaro]

Jig McGalliger님이 먼저 게시:

There is a max amount of filter time one can hold.

Yes, I understand, but then why can't I pick up any more filters? When I stocked up at Riga I had about 40 minutes... Slightly less, I think... So as I use up my filter time, I go through all the levels and have less and less air, shouldn't it be logical that I am far below my limit and should be able to pick up more filters? Well I can't. This is what I don't understand. :(

I scavenge constantly. It's what I do most, and I don't want to finish the game without having sniffed around every little corner I could possibly get access to. Filters, filters, filters everywhere and the game just doesn't want to pick them up.

I reached Outpost with like 10 minutes left of air because the game wouldn't let me pick up any filters at all. And then I left Polis and chocked to death while being chased around by nosalises, desperately trying to find filters lying around on the floor (even though I knew I wouldn't be able to pick them up anyway!). Not fun.

[Proph]

Hey jpblazaro,

If you check out my guide you will see that once you are around the 40 minute mark you can't pick up any more filters because you are at the max. When you have less filter time you'll be able to pick up more.

[jpblazaro]

Hey Proph... Thanks, but I did read your guide, including the part about the 40 minutes max. I understand all of that. What I don't understand is why the game never lets me pick up any filters whenever I find them, even when I only have like 5 minutes left of air.

Proph님이 먼저 게시:

When you have less filter time you'll be able to pick up more.

It should certainly be that way, but that's what's failing in my game, and I don't understand what it might be that I'm doing wrong.

It makes sense to me that e.g. if I have 39 minutes left and I find a 2-minute filter, I can't pick it up because it would put me over the max. What doesn't makes sense to me is: I go through all the levels, I'm gradually using up my air (30 minutes left, 20 minutes, 10, 5, 2, 1...), I find a massive amount of filters along the way, but the game never, and I mean never, lets me pick them up, regardless how much time I have left.

I've been trying to read more about it and it seems I'm not the only one out there who's had this problem.

I do appreciate your taking the trouble to make this FAQ and your having replied to my questions, in any case.

[MrWafWaf]

Hey guys, great article to begin with but 1 question that I feel a lot of people want to know but I can't seem to find is; In Metro 2033 Redux, the watch beeps at 1 minute remaining telling you to change filters. If i change my filter when the 1 minute beep happens do I lose 1 minute of filter use or does it get backlogged for later?

[Proph]

I can't speak for Redux specifically, but you should not lose that "remaining" one minute since the game tracks your filter time by minutes, not by the number of filters.

[ACE]

how do i get a not broken gas mask?

[Roadbobek]

what does pressing t even do?

[vlad[54rus]]

Looks like the limit is 3-4 filters to pick up by yourself and 5 when buying from a merchant.