There are no sure answers for ice being safe. The general standards for safe ice are a good rule of thumb, but with variables in weather and water, ice fishermen need to always be cautious.
There could hardly be a more desperate predicament than to fall through the ice and have no one around to help you.
This is particularly discouraged in Wyoming due to fluctuating water levels in reservoirs and our wind impacting ice conditions.
If you do fall through the ice, a PFD will help you stay buoyant while grabbing the ice picks to get a grip to pull yourself up on the ice.