Please do your homework on all 3 treatment options. There are 3 for hyperthyroidism, which are:
surgery to remove a portion or the whole thyroid gland
radioactive iodine ablation of the thyroid gland (also called RAI)
What is the CAUSE of your husbands hyperthyroidism? Have they tested him for the antibodies that cause Graves disease? Graves is the number one cause of hyperthyroidism, and TSI (thyroid stimulating immunoglobulins) are the antibodies that cause Graves. A simple blood test can check this out for him.
Personally, I feel that RAI for hyperthyroidism is barbaric, but that is just my opinion.
If your husband has the RAI ablation of the gland, then he will be emitting radioactivity for several days. I would think that he would be exposing the other people on the plane next to him.
I highly recommend the book "Thyroid for Dummies" by Dr. Alan Rubin. You can skip directly to the chapters on hyperthyroidism....it is an education on what is wrong with your husband and explains the treatment options too.