In Europe, ETSI regulations set a 0.1%, 1% or 10% duty cycle, uplink or downlink, depending on the band.
See for example section 7.2 Technical parameters and implications on spectrum of Technical characteristics for Low Power Wide Area Networks Chirp Spread Spectrum (LPWAN-CSS) operating in the UHF spectrum below 1 GHz or section 2. Applicable Bands: Overview of AN1200.10: ETSI Compliance of the SX1272/3 LoRa Modem.