One sprinkler head puts out more water per minute than a burst pipe.

Sprinkler systems are isolated at a control valve that is usually locked, monitored and alarmed. Closing it without telling anyone takes the building out of fire protection, which is why in most buildings only the manager or the fire service does it. Your job is to report it immediately and get people and belongings out of the water.

In a house with a residential system there is normally a single shut-off near the water entry, and the same warning applies: once it is closed, the house has no sprinkler protection until someone resets it.

A single residential head discharges on the order of tens of gallons per minute. Ten minutes before someone isolates it is therefore hundreds of gallons, released at ceiling height and spread across the whole floor rather than pooling at one point.

Because it falls from above, it reaches the tops of partitions, the insulation in the ceiling void and the electrical fittings, which are the three places a wall-level flood never touches.

On an upper floor it then finds every service penetration and goes down. A sprinkler event on the third floor routinely produces damage on the first.

The water in a wet sprinkler system has been sitting in steel pipe since the system was filled. It is not contaminated in the sewage sense and porous material can usually be dried, but it is heavily discoloured and stains fabric and plaster in a way that ordinary supply water does not.

Photograph the staining early. Insurers settle textile and decorating claims from those photographs, and the stain darkens as it dries.

Accidental discharge is a sudden and accidental escape of water and standard wording answers for it. Discharge that put out an actual fire is a fire claim, which is a different set of numbers.