10G BiDi Transceiver set (S+2332LC10D) minimum distance

Hello!

Regarding the S+2332LC10D BiDi 10G transceiver set, I can see from the specifications that the maximum run length is 10km.
My question is regarding minimum run length; what is the minimum distance / run length that would be safe and supported using a set of these without an attenuator?

Thanks!
Goodbye