If someone says,
あなた は Chris-さん です か。
Are you Chris?
Do you answer
That's because these endings usually convey a kind of relation: for instance,
Unless it is some sort of elaborate joke, you should not put -さん after your name.
Maybe a story could be helpful...
Once when writing the minutes (議事録 gijiroku) of a meeting, I had to write the list of the participants at the meeting. I wrote it like this, and then sent the email.
As soon I sent this email, the reaction from my coworkers was: "LOL, he put さん to his own name". And tons of 指摘 shiteki afterwards.
So yeah, you should never put -san after your name unless you're trying to be funny. If you want to try to be funny, send an email within the mailing list to another coworker without putting -san to his name. Lots of shiteki guaranteed.