You can be tested and receive a cert. stating you are free of STD's and it is good until the next time you have sex. Nothing more.
In 30+ years no one has ever asked us for one and we don't carry one with us anyway so it would do you no good.
I don't know anyone that carries their health cert. even if they did have one.
There is no guarantees in life or this Lifestyle.
Honestly, if you are that concerned you might want to really think about even being in this Lifestyle.