Making a cheap chemical fume chamber

I will be working with sulfuric acid to decapsulate chips, and this generates sulfur dioxide gas. I have an idea about bubbling the gas through hydrogen peroxide to reform sulfuric acid, but I can't be guaranteed that the reaction will use up all the sulfur dioxide. Besides, in the initial experiment, I'm not going to try to reuse the sulfuric acid.

Anyway, sulfur dioxide is toxic, but it can removed with an activated charcoal filter. I could set up an air filter and try to suck all the fumes through it, but instead I had an idea when I saw this [abrasives blast cabinet at Harbor Freight] (US $170):

It has a circular hole in the back and one on the side, so maybe I could adapt this as a sort of contained chemical fume hood. A fume chamber.

It doesn't have to be air-tight because I'm going to suck the air from it, which means that air has to be provided from somewhere, and random openings and leaks are just as good as anything.

I didn't need that abrasives chute at the bottom, so instead I took the support, covered the hole with a thin sheet of steel (held down with VHB tape), and used that as the bottom piece. I did have to drill holes in it to match the chamber. I also applied a line of foam tape to the outer edge to seal it.

I used a 4-inch dryer hose adapter thing on the back. The hole in the back is just a bit smaller than 4 inches, so I had to cut off part of the adapter so that I could fit it flush. I sealed with silicone caulk and screwed it into place.

Also, without the funnel, the thing was wobbly so I put some 1x6 wood supports in.

Amazingly, these Veva "[Premium Carbon Activated Pre-Filter 6 Pack for Germ Guardian Air Purifier Models AC5000 Series, Replacement Pre-Filter C]" (US $10, Amazon) are exactly the right width to fit in this duct that goes to the hole in the back. They are thin, so I had to use three of the six from the back.

The light provided in the chamber kit sucked, so I bought a [strip of LEDs] and installed those (US $16, Amazon, with [right-angle connectors] US $8, Amazon). It really brightens the interior up nicely.

Next, the gloves included with the kit were for abrasives, but I wanted nitrile gloves. I found these [Showa Atlas 772 M nitrile elbow-length gloves] (US $12.50, Amazon). I cut off the elastic at the end, stretched them over the large glove holes, and secured with the provided hose clamps.

Left: Showa elbow-length nitrile gloves. Right: The gloves provided in the chamber kit.

Left: Showa elbow-length nitrile gloves. Right: The gloves provided in the chamber kit.

I attached my laser cutter's fume extractor fan to the chamber, and when I turned it on the gloves inflated. That's not great, because if I set everything up inside and then turn on the fan, the gloves would knock everything over. The solution was to put the switch for the fan inside the chamber. That way I could put my arms in the gloves and then turn on the fan.

Total was about US $250, not including the fan or the hoses. Of course, this isn't a real fume hood. I have no idea if the paint would react with things. Certainly if acid spills, it will eat the metal, but I can mitigate that by keeping a box of baking soda in the chamber. But I think this will suit my limited purpose.