If you are REALLY worried about:
1) getting all the gunked up juice out, and
2) making sure it is biologically clean and sterile
Soak it in grain alcohol for a few hours. Then shake or blow it out, and let it air-dry for a few hours and dry-burn the coil.
Washing in water will NOT sterilize a metal object unless it is boiling hot and exposed for several minutes.
Hot tap water will not even come CLOSE to sterilizing your gear. There is "clean" and there is CLEAN. Bacteria and viruses are NOT kiled by hot tap water, and rinsing something in running water for a few seconds will NEVER get down into all the little nooks and crannies of something as complicated and tiny as an RBA.
If you REALLY want to get your gear clean, buy a bottle of Everclear and soak your metal parts in a little cup of that. I soak ALL my gear--Vivi Nova parts, attys, cartos, RBAs even drip tips--in pure alcohol. I vape about 2-3ml of juice a day, and clean out tanks about every second or third refill, and attys get cleaned about once a week if I use them.
Plastic parts just need a quick dunk--a few seconds is sufficient (you need to be careful with plastic, because pure alcohol can make it cloudy or can mess up the finish if it has a clear coat of CA like some custom-made drip tips).