Which of the following is NOT a type of sprinkler system?

Automatic pressure system is not considered a recognized type of sprinkler system in the context of fire protection. Sprinkler systems are classified primarily into different categories based on their design and operational characteristics, such as how they store water and how they are activated during a fire.

The standard wet type system involves pipes that are filled with water at all times and water is discharged through activated sprinkler heads when a fire is detected. The standard dry type system is designed for areas where the temperature may fall below freezing, using pressurized air to prevent water from entering the pipes until a fire occurs. The deluge system operates differently, having open heads that release a large volume of water over a wide area when triggered, typically used in high-hazard locations.

The classification of sprinkler systems as standard wet, standard dry, and deluge reflects their intended use and operational mechanics, unlike an "automatic pressure system," which does not align with established sprinkler classifications. This term may relate to other pressure-related systems but does not fit into the recognized categories for sprinkler systems used for fire suppression.