Ok, I'm a little confused as to the options regarding gas masks, respirators and so on.

I can buy a gas mask (as per BBB) which...renders me immune to air-vector toxins, gases and irritants?

A respirator can be fitted with a pressure gauge to enable a character to use oxygen tanks.

The Atzlan sourcebook mentions air filters which...reduce the power of Gas attacks and air-based toxins?

Is there a definitive answer in a book I've overlooked?

-Siege

Like most chemical stuff, gas masks were relegated to M&M. You've a couple of options for protection, in addition to what you noted.

You also have chemsuits, which are described on p 293 BBB but priced on 295 BBB. It's not outlined what those suits are capable of, I'd say they should reduce the power of contact toxins by their rating, maybe air ones too if the GM is feeling really nice.

You also have Hazmat suits(Pg 116 M&M), which compeltely protect you from contact and inhalation vectors. The description of gas masks is buried in the description of Hazmat suit's, stating that if you wear a gas mask and air tank you're immune to inhalation vectors. That happens to be bullshit because, as Austere pointed out about, you really just need a gas mask.

Oh goody, house rule time!

Edit: Thanks for the input guys.

-Siege

No like you ever use those...

Depends on the filters you have, plenty of advanced chemical agents have stuff added to deliberatly clog gas mask filters (that's why your chemical warfare suit comes with a lot of spare filters, you should be able to change the filter without compromising the integrity of the suit).

Also, breathing through a filter can be pretty hard work, try layering a lot of blanket in from of your mouth and breathing through that. Now, try running around while doing that.

The independant air supply can also protect you from places where there isn't enough air to breathe to begin with (in/near a fire, for example).

Question: what's the range of the chemical attacks? From low to high-end?

-Siege

Hah! The table in M&M page 106 mentions chem suit air filters subtract the suit's rating from the Chemical attack.

Grrrr.

-Siege

As in, what the least nastly stuff to the really nasty stuff?

Starting at the low end are thing with a high letal dosage, that must be breathed or absorbed the mucous membranes, and don't deploy that well, and don't last that long.

Sample Chlorine gas used during WWI, it can be 'tricky' to actually kill someone with it (though plently of people were blinded or had their lungs permanently damaged). not to mention Cl2 blows away rather easily. Also usually listed as a 'low end' chemical weapon is Hydrogen Cyanide, sure it's plently lethal but it's hard to get to stick around. There was a bit of research in making HCN 'fog' that would deploy better, but the nerve and blister agents were much better alternatives.

Next are are the blister agents (Mustard Ges, et al) they tend to be 'greasy' so they stay deployed longer, and stick to the targets better. They can usually be absorbed through the skin , though the letal dosages are higher that just breathing the stuff.

Last are the nerve agents which have incredibly low lethal dosages, even when abosrbed by the skin.

The nerve agents are either unpersistent (Sarin) or highly persistent (VX). Also, the modern 'weaponized' chemical agents (as opposed to what might come out of an industrial accident) will tend to have extra stuff added to them the promote things like clogging gas mask filters, eating away at chemical suits, and so so on.

FAS should have a lot more than this.

Gas masks without their own airt tanks are filters, they keep you from inhaling nasty stuff, like chlorine or phosgene gases but if the smoke is too think, like in a house fire, there isn't enough clean air to breath, for that you need an air tank, like a firefighter.

These do not defend against contact gases, like mustard gas, which can be absorbed through the skin, for that you need a chem suit too.

I finally dug out my copy of M&M and checked the chemicals listed.

Take a look at my quickly sketched house-rule for gas masks.

Gas masks!

-Siege

Dunno, the rating system seems a bit too complex for my taste.

I would assume that a rating 4 military gas mask + MOPP suit will protect you from most everything you would encounter on the battlefield (at least of a while). Otherwise, why would you obther making them?

(I'm not sure what powers chemicals tend to come in, isn't neurostun-VII 7S - contact? This would mean that it would be 3S - resist with body; our average trooper with body 4 will be taking a moderate wound. Now add to the fact hat that was 3-6 seconds of exposure, and the war is going to go on for weeks...

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MOPP Gear

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Mostly due to the fact that most people won't be expecting 'SR: world war 4'. Since chemicals should not be that common place the rules should, probably be a simple and as player friendly as possible. Finding out that my MOPP gear won't protect me (as a player) would tend to make me thing that the GM is out to get me, rather than thinking that my MOPP gear was not up to the job. I don't expect my players to know the power level of chemical X , just that they might need 'some gas masks and stuff' to avoid it. A better 'stressor' would be the skill in actually using this stuff.

(Notice the most runners have no training in this sort of thing...) Adding a knowledge skill that lets you use NBC gear (suits, detectors, etc) is probably appropriate. Assume most well trained (military) personnel will have this at 2-3. People who work in medical training or work in certain hi tech production facilities might have half dice. (Biotech, certain B/Rs as complementary when using MOPP gear?).

On of the things to really notice about MOPP gear is that it really jacks up your TNs.

In MOPP-4 you're looking at something like:

Sight +2
Hearing +4
Touch +6 (or more)

All physical TNs +1 (soon +2 due to fatigue).

In the SR age, things might be a bit better.

So instead of a variable rating, just two fixed values:

Civilian model respirator: -2 to chemical Power, inhalation vector

Military model respirator: -4 to chemical Power, inhalation vector

If an oxygen tank is used, the wearer is immune to inhalation vector chemicals.

Better?

Not quite -- back to the drawing board.

-Siege

well, theres always the internal air supply. add a gas spectrometer, biomoniter, or the like, and your set. just hope it dosent take stress and explode.

Air or blood filtration cyberware. does anyone ever get that stuff? technicaly blood should make the others redundant, since air or ingested typicaly have to get to the blood (via lung or stomach) before they effect you.

and you could always have an air elemental blow away any gas back to the enemy (and the enemy mage could do likewise).

The respirator is weak, but its better than nothing. also usefull when the troll has mexican for dinner.

In the BBB, a "respirator" is an independent air supply with a face mask, yet it only reduces the Power of damaging gases by 2 and the damage code by 1?

The "Respirator" is, essentially a gas mask with some spiffies.

The MOPP gear is basically the haz-mat suit or the X-E suit.

The chemsuit -- something fundamentally accessible to all audiences for the "hard rain" has a better air filter than the respirator.

And the chemsuit is easier to obtain.

-Siege

Good system you have there. Might buff it out with the ability to provide extra protection against some chemicals with either increased price and availability, or by making it less effective against others.

How would you handle Green Ring 8(Pg. 119 M&M) and Seven-7(Pg. 121 M&M) under your system? Those chemicals designed to penetrate chemsuits, resulting in chemsuits just increasing the speed(IE Making it take longer to take effect) by 2 turns. Same thing as your gas masks or they only act like that vs civilian-grade gas masks?

Will any sort of armor or gas mask protect you from FAB-III?

Just make sure that any 'standard' chem suit you come up with will protect you against the stuff that chem suits will protect you against today: HCM, Cl2, Sarin, Blood and Blister agents, and so on. Chemical suits will have not gotten any worse.

I'm gonna re-write the "chemsuit" which currently is a glorified pair of golashes instead of a full-body suit which is how I always interpreted it.

Serves me right for not reading the description beforehand.

-Siege

Re-writing the gas mask rules, take 2.

SR Index reference

-Siege