To limit the probability that plumbing equipment will be inaccessible for maintenance, which could lead to blockages or failure, which could lead to leakage or flooding, which could lead to damage to the building or facility.
To limit the probability that plumbing equipment will be inaccessible for use, which could lead to delays in accessing system controls such as shut-off and pressure-reducing valves, which could lead to excessive leakage or flooding, which could lead to damage to the building or facility.