Hope this helps... (the sensor is IP44 rated so...)
An IP44 fitting can be installed anywhere within bathroom zones 1, 2, or 3. Zone 1 is the area above the bath to at least 2.25m (7' 4"# from the floor. If the light is 240V then a 30ma residual current device #RCD# must also be used to protect the circuit in this zone. #check the consumer unit, if it's 17th edition, it'll already meet that requirement#.
Zone 2 is an area stretching 0.6m #1' 11"# outside the perimeter of the bath and to a height of 2.25m #7' 4"# from the floor. In addition, it is good practice to consider the area around a wash basin, within a 60cm #1' 11"# radius of any tap to be considered as zone 2.
Zone 3 is anywhere outside Zones 0, 1, and 2 and where no water jet is likely to be used. If there is a likelihood of water jets being used for cleaning purposes in zones 1, 2 and 3 a fitting rated a minimum of IP65 must be used.
Where MUST I NOT install my IP44 bathroom Light?
You cannot fit an IP44 light inside the bath or shower itself. Any fitting used in this zone #Zone 0# must be low voltage #maximum 12V# and be rated at least IP67 which is total immersion proof!
As bathrooms are consider a high risk area, work in bathrooms should be undertaken by a registered competent person!