Designing Complex Hazards
A good complex hazard often requires disabling multiple components or otherwise interacting with the encounter in some way. For instance, while the haywire autopilot can be remotely reprogrammed with a challenging Computers check, characters who want to use Piloting or Thievery to override the autopilot will first need to board the vehicle using Acrobatics or Athletics.
Building Routines
If you create a hazard that can't consistently attack the PCs (such as an electric fence, which only damages creatures touching the fence), it can be deadlier than normal in other ways.
The hazard should have as many actions as you feel it needs to perform its routine. If you split the routine out into several actions, you can also remove some of the hazard's actions once partial progress is made in disabling or destroying it; this can give the PCs a feeling of progress, and it can encourage them to handle the hazard if it appears in an encounter alongside creatures.