Comp Wash
Allison/RR prescribe the water wash at the end of any day's flying in the UK. The rationale is based on their assessment of a 'hostile environment' defined as anywhere in UK given that the maximum distance from the sea on our island is 70 miles. In addition to this are the sulphur-based contaminants emanating from industrial sites (albeit less than previously).
The advice is wise, if a compressor lets go, it will be inconvenient (of course) and seriously expensive. ~ VFR