Three Dangers of Redundancy

Normal Accident Theory articulates three dangers of redundancy, summarized by Scott Sagan as follows.

  • Redundancy increases complexity, generating “common-mode” errors. Example: Fermi Reactor safety device added at last minute breaks off and blocks coolant pipe.
  • Redundancy may lead to decreased sense of responsibility among workers. Example: Diffusion of responsibility among AWACS operators led to no one passing needed information to F-15 pilot. See Bystander Effect
  • Redundancy may lead to increased production pressures due to perceived safety. Example: Injuries increase when helmets added to a sport.


Examples and breakdown from “Learning from Normal Accidents” (pdf)

Normal Accident Theory see accidents as “normal” and has related insights.

A related issue is Alarm Fatigue

Source: Three Dangers of Redundancy


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s