Like graywolf I have used enamels for years and have not died once. Risk is from inhaling the volatile components, mainly the bits that smell, and if it really worries you go to your local industrial safety shop and buy a suitable disposable mask. Looked after these will give over fifteen hours service and cost under ten bucks.
As you are in the land of Oz the ambient temp may be a problem. Paint dries faster the hotter it is, so if you are painting in mid-summer in Alice the paint might be dry before you get it as far as the model.
If possible mix your paint in an old paint bottle, take some out and cap the bottle till you are ready for some more. If you are painting armour divide the model into sections, in the case of a tank, say lower hull, upper hull and turret. Just paint one section at a time.
Make sure your paint is fresh and of the right thickness. As you use a pot of paint it tends to thicken and will dry quicker, and be harder to apply. A little thinning with turps may help, but as the thinner is itself volatile it will evaporate off over time.
Hope this helps. Dave.