what is 3.1 certificate ?

what is 3.1 certificate ?

can i able to see 3.1 certificate ? what is the format of certificate ? can i see same for pulsation dampener ?

A 3.1 certificate relates to an inspection certificate that is given for products that have been tested in accordance with DIN-EN-10204 (see the links below).

For specific information on what information needs to be in the certificate you will need to refer to the standard (second link).

From what I can determine this certificate done as a letter that demonstrates what testing has been done, the results of those tests, who did the test, and when the testing was done.