How to prevent infestation.

[Aristocat]

1. Give Homeless Bugs Place to Live
When ai throw hives, it checks per square. This means if 50 square in your colony is overhead mountain and you have 150 square mined area outside of base, and ai throws 10 hives, only 3 hives spawn in your base.

2. Sweet Cold Death
Ai don't throw hives at spot that's temp below -17c.

This can backfire though, if you have 300 square mined area but only sleeping quarter is above -15c, ai will instead shove all of it into your ass.

3. Common Sense
Ai threw hive at your bedrooms and dinning room and everyone is slaughtered? Or you know, don't build essential facilities inside mountain, you knew they were going to spawn, they spawned and everyone is dead. Doing same thing and slaughtered over and over again isn't called "rng screwed you over", it's called idiocy.

https://www.reddit.com/r/RimWorld/comments/4h4scz/how_to_prevent_infestation/