Import point with point description

Dear All

I am trying to import survey data in PENZD format through ASCII import. Is there any naming convention to write/import point description. For eg:

S.n                   E                           N                             Z                             D

1                     1000                    1000                      99.85                    TBM

To import this point along with TBM as point description what should i do? please help in naming convention of feature code.

thanks in advance.