I'm not wearing it now, I can smell the fumes from outside, and I AM getting a headache.
This gas mask is very similar to the successful British Small Box Respirator used in WW1. Inside the familiar cloth hood with goggles it had a nose clip, a mouthpiece and a hose to a can full of charcoal and soda lime. My canister only uses carbon as the absorbing agent since I'm not concerned about "acid gases". If you need to filter out military poisons or chemicals similar to them, add the soda lime and other ingredients.
There are many avid gasmask collectors and enthusiasts. Images and information about gas masks is very abundant online. The French collector's site gasmasks.net has an amazing pictorial database covering gas mask evolution in all the worlds armies.
In 1942 Time Magazine published the following piece:
"Homemade Gas Masks
Monday, Sep. 07, 1942
An emergency gas mask that can be made at home was demonstrated in Manhattan last week by the American Women's Voluntary Services. The necessary materials can be found in almost any house: a bathing cap, a small tin can, the transparent cover from a powder-puff box, a bit of wire net (from fly swatters), two handkerchiefs, elastic ribbon, adhesive tape, and (from the drugstore) a few ounces of activated coconut charcoal and soda lime. The principle behind the homemade mask is simple; the assembly is more difficult. The rubber cap is fitted snugly over the face and two holes are cut in it; one for the powder-puff cover (to look through), one for the tin-can respirator. The ends of the can are removed, replaced with the wire net. Inside the can go the chemicals (two parts activated charcoal, one part soda lime) wrapped in the handkerchiefs. All openings in the cap are hermetically sealed with adhesive tape. An elastic-ribbon harness holds the mask on tight. An alternative model makes use of rubber baby pants (see cut) instead of the bathing cap.
When carefully made, this improvised gas mask is effective against all known war gases. But the A.W.V.S. and the War Department are leary of inexperienced workmanship. The least carelessness in fitting the parts of the gas mask together would permit gas to enter. The A.W.V.S. recommends that all such masks be made under its supervision.
An even simpler mask is advocated by Dr. Kearney Sauer of the Los Angeles Citizens' Defense Corps: two twelve-inch squares of bed sheeting with a quarter-inch layer of baking soda between, held in even distribution by crisscross stitching. Dampened and held firmly over the face, this napkin will give temporary protection against any gas, according to Dr. Sauer but not the Army.
The simplest device of all consists only of a beer can filled with absorbent material and a clothespin to clamp on the nose. It is approved by no one except its inventor, Chemist Vernon Bowers of Baltimore, Ohio.
Step 1: 1942 - Popular Science
So says a December 1942 Popular Science article on how to make that same type of improvised gas mask.
The following information may help you understand the instructions better.
"10/20 mesh" and "4/10 mesh" specifies the grain size of the crushed charcoal.
Sorting grains by size is called "screen classifying". To do it you put a stack of sieves on a sieve shaker with the coarse one on top. To make 10/20 you'd put a sieve with a 10 mesh (ten wires per inch) screen on top of a 20 mesh sieve. You'd pour your crushed charcoal in the top and shake the stack. The 20 mesh sieve would fill up with the good stuff, you'd dump that into your gas mask cartridge.
In other words the charcoal grains they use are between .05" and .25" diameter. I've read that that resistance to breathing while doing strenuous work is the major problem with gas masks. A mask made with such large grains might have very easy air flow.
Soda Lime ( w'pedia ) is calcium carbonate (lime) reacted with aqueous sodium hydroxide (lye). It absorbs carbon dioxide among other things.
Carbon tetrachloride is dry cleaning fluid, very common in those days when synthetic fibers were rare and many people wore clothing such as suits that would be harmed by laundering in water.
Star says "CCl4 note that carbon tetra chloride is carcinogenic like pasta sauce is red, and you probably don't want it in your house or on your hands or anywhere"
The text of the article continues: "
This type of mask, designed by Dr.Simon L.Ruskin of New York City, is intended to protect the wearer only against the common, known gases used in chemical warfare. It is useless against smoke, illuminating gas, and carbon monoxide (automobile exhaust).
How such a mask is made is shown in the accompanying photographs. Use a heavy bathing cap, not a thin one. Make joints airtight so that the wearer can breathe only through the canister.
The physical filtering agent in the canister is activated granular charcoal, which can be obtained at drug stores and wholesale drug houses. To test it for activity (the ability to take up and hold gases), place a small amount, such as a tenth of a gram, in the palm of the hand and pour on it five drops of carbon tetrachloride.The charcoal should become warm.
If not, it's unsafe. Either one half 10/20 mesh and one half 4/10 mesh, or the coarser charcoal alone, may be employed.
With it mix one half as much coarse-mesh soda lime (sodium calcium hydrate), also available at drug stores. Pack the canister solidly. No air must enter without passing through the charcoal. Do not forget to seal both ends of the canister with tape or heavy waxed paper. If left unsealed, the charcoal will absorb moisture from the air until it is saturated, and the mask will be useless. Unseal the canister only when the mask is to be put on for protection against gas. Once the mask has been used, the canister must be refilled with fresh charcoal and soda lime. "