Yes, no problem! All the Purus gullies have a removable water trap that is easy to clean. Just be careful with tools in the gully so you don't move the clamping ring out of position and that gasket are undamaged and in correct position.
To make it easier to assemble the gasket can be greased using soapwater etc. To just make a fast rinse of the water trap, flush with cold water after you have showered in estimatedly 5 seconds staight to the gully.
Make sure that there is water in the water trap, if the gully is not cleaned properly in a while there will be sope residue etc. and that can contribute to bad smell. Clean the gully with germicide and rinse properly afterwards. If it's for example a summer home we would recommend the NOOD, read more about it here.