What font size to use for Large Print?

[LovetoWrite]

Hi,

I'm writing a book for my parents and I want it to be in large print. They have a difficult time reading newspapers, books and mags. I don't want this book to be a strain on their eyes.

Could someone tell me what size font is generally used when a book sold as large print?

[CaoPaux]

Check out the ADA and your local government sites. E.g., Googling "ada large print criteria" found this: http://www.ga.wa.gov/ada/lgprint.htm

[LovetoWrite]

Thank you CaoPaux, that information was perfect. :)