Sensor Mq-135 maximum distance

what is the maximum distance (in meters) sensitivity of the mq-135 sensor? please anyone tell me :(

Do you have a link to the datasheet?

Note: such a gas sensor works on the place it is mounted. It cannot measure the concentration in the far corners of a room. However you can assume that if there is enough movement of the air/gas due to convextion or so that air/gas mixes and spreads evenly quite fast