I am getting to the point where I need to consider the plumbing of our sink unit which will have a washing machine on one side and a dishwasher on the other. I am considering one of these for the two waste hoses

https://www.screwfix.com/p/mcalpine-...ite-40mm/6295p

Any gotchas such as siphoning or other issues using this type of fitting? Currently the dishwasher feeds into something like with no particular issues.. The washing machine feeds into a stand pipe type but because of the shape at the back it prevents it pushing all the way back and it is going to be awkward to place a similar type in the neighbouring cupboard.

Richard