use of octothorpe in X12 copy statements

I’m going to be building an Xlate for an X12 interface ..

Just thought I’d ask before I built it .. and learned for myself (grin).

is the symbol # usable in X12

e.g.

1(0).1(0).0(0).NM1(0).#9

or

1(1).1(0).0(0).REF(1).#2

Thanks

Dennis