Bails said...
Also I broke an alley boom once and I could see the evidence of salt corrosion on the break. Aluminium should always be washed because it corrodes.
The booms often break at the extension clip pin holes.
This is because the pins are always stainless steel and the boom is aluminium which sets up an electrical cell and the ally disolves to protect the stainless steel pins. This means that when the boom finally breaks the pins will still be in mint condition. Great!
Unclip the boom extension pins when not in use, particularly if stored for a long time, like over winter.
If you store your boom with the clips in place, check out the corrosion around the holes that the pins were in and compare it to the others and you will see what I mean.
I never wash any of my gear and it still lasts years.