Question about ms max power parameter.

Hi Folks. I have a simple and straight forward question: in the openbsc.cfg i find a parameter "ms max power" which is set to 15 dBm (apporox 30mW) by default. http://openbsc.osmocom.org/trac/wiki/osmo-nitb_VTY says the following: "maximum transmit power (in dBm) to be used by MS in this BTS. This is used in the System Information on the BCCH as well as for the MS power level at the time a dedicated channel is activated." My question is how low may i set ms max power level? Is 15dBm already the lowest possible minimum or can i set it down to 1dBm if i like? regards Philipp