Answer: Dear John,
Rose Shield is not registered for edible crops. Lime Sulphur has no registration for use on vegetables.
To control the rust on your broad beans and garlic, the product to use is either Yates Fungus Fighter or Leaf Curl Copper Spray. There is a 1 day withholding period with both these products.
If you find you are having rust problems every year, it would be a good idea to practice a crop rotation and this will help to prevent this fungus from re-appearing on your plants.
Ensure that the plants receive ample sunshine and water them in the morning rather than in the evening so as not to encourage development of this fungus.