Max EIRP regulated from FCC (US) and ESTI (Europe)

FCC (US)

Transmitters in the 2.4-GHz band can be used indoors or outdoors.

• The power emitted at the transmitter must be limited to 30 dBm 
• the EIRP limited to 36 dBm. 

An antenna gain of +6 dBi is assumed. However, there is some flexibility according  to the following two rules, based on the intended spread of the signal:

■ Point-to-multipoint links
—Where the  transmitted signal propagates in all directions, you can make adjustments according to a 1:1  rule. For each dBm you remove from the trans-mitter, one dBi can be added to the antenna gain, as long as the EIRP is no greater than 36 dBm.

■ Point-to-point links
—Where the transmitted  signal propagates in one general direc-tion, you can make adjustments according to a 3:1 rule. For each dBm you remove from the transmitter, 3 dBi can be added to the antenna gain. The resulting EIRP canexceed 36 dBm but cannot be greater than 56 dBm.

ETSI