Boiling the bark can be a huge mess. If you're going to do it, put it in a big rubbermaid & pour boiling water over it. You could even use a weak bleach/water solution followed by a thorough rinse.

Another thought - since reptile bark is made of chunks of fir bark, it doesn't tend to have quite the absorbancy of a finer-milled substrate. If you're bent on using a natural substrate you may want to look into cypress mulch, which can typically be purchased for $3-$4 per bag at a Home Depot/Lowes type garden center. Just make sure you don't get anything containing cedar, which is toxic.

Food for thought.

K