I have a mould problem in my basement which I suspect is responsible for the bronchitis I have been suffering from. Antibiotics have dealt with the bronchitis and now I am about to deal with the mould however I don’t want to expose my lungs to it anymore. The local surplus store has Israeli gas masks (with canisters) for about 30 bucks. Will these offer protection against spores?
I believe gas masks operate using two mechanisms:
Have chemicals react with an destroy the gas
Absorb the gas into activated charcoal and lock it away
They are not specifically designed to deal with spores/dust, but there is a filter designed to stop the activated charcoal dust being drawn into the mask itself, which will also strip out the spores.
However, I would advise you to find someone who really knows about mould and ask their advice. One the one hand you may be going over the top and a $10 paper mask from a hardware store would be fine, on the other hand if you a severely allergic you might need something to keep the spores off your skin (similar to the fine-weave overalls used for asbestos removal).
In the Navy I learned more than I ever wanted to know about gas masks and happily let most of the info leech out so I can remember more importaint stuff like Monty Python.
I honestly can’t say the filters in the canisters will block mold spores, it’s all about the micron size. I’d only try this if the canisters are still sealed in the coffee can like container from the manufacturer. Exposed to the air and elemants like humidity the filter will break down and not be as effective. Even in the original sealed container they have a shelf life of 10 to 12 years.
—a funny aside—
During shipboard training and emergency egress drills I would always tell the new guys do not ever ever try to use a gas mask in a smoke filled emergency like from a fire. You will still die from smoke inhalation. It will be the cleanest smoke you could ever imagine but it will still kill you from lack of oxygen.
An N95 level disposable repirator will stop anything larger than .3 Microns, so it’s stop spores. You can get a box of twenty on Ebay for pretty cheap. Cheaper than an Isreali gas mask at least.
Thanks for all the info. 
Almost any military-grade gas mask will have been designed to block B. anthracis spores. Unless mold spores are radically smaller, it should do fine. As others have said, You would have to ensure that the filter element was new. Wearing it around your house, it would get saturated eventually just from everything else in the air, and you would have to replace it often.
IMHO, you’d be better off with a US military surplus mask, for which newer filters are available, than those old Israeli ones.
Or get rid of the mold, which is really the only solution to the problem.
It seems like overkill to me. From what I have read gas masks are tiring to breathe through. Wouldn’t you first want to see if a regular dust mask, or something similar, would stop the mold?