What is the main purpose of a containment cable in garage door springs?

The primary function of a containment cable in garage door springs is to prevent the spring from causing injury if it breaks. Garage door springs are under significant tension and can store a large amount of energy. If a spring were to break, without a containment cable, the spring could whip around violently, posing a serious risk of injury to anyone nearby or causing damaging impacts to surrounding structures or vehicles.

The design of the containment cable ensures that if a spring fails, the cable will contain it, effectively preventing it from becoming a projectile. This safety feature is crucial for reducing hazards associated with spring failure, thus protecting both individuals and property. Other options, while they may relate to garage doors in different contexts, do not address the specific safety purpose that containment cables serve.