FX103 SERIES | SITE VISITS FOR INSPECTORS & INSURERS
How do you inspect for sprinkler orientations?
Continuing on our tour of an existing facility from the perspective of an insurer.
This is an important item to check during a visual inspection. The sprinkler orientation is of utmost importance as this will determine the proper water distribution pattern. If the spray pattern from the sprinkler is not correct – the system won’t throw water to the hazard and could be compromised by additional sprinkler activations, or worse, fail to suppress the fire altogether.
One important thing to remember is that the sprinkler deflector should be installed parallel to the ceiling and should be directed to discharge water towards the ground.
This means that pendent sprinklers need to be installed in the pendent position and upright sprinklers in the upright position. It seems obvious, but wrong orientation is sometimes found in the field.
This is particularly true in countries (mostly outside the US) where conventional or old-type sprinklers are still commonly used.
There is no specific orientation for conventional sprinklers, they can be installed as an upright or a pendent. However, this causes confusion by some contractors when they then use spray sprinklers, which are created and intended for one direction only.
This problem is less frequent with sidewall sprinklers as their position is quite obvious, in particular for the horizontal sidewall sprinklers.
With vertical sidewall, as some of them need to be specifically installed upright or pendent, the same confusion may be encountered as for standard spray sprinklers.
How can you check the proper orientation from the ground floor?
By looking at the deflector.
The deflector of an upright sprinkler is a full disc (when seen from the floor), with no opening.
The deflector of a pendent sprinkler is a disc with many holes, just like a pizza where you have taken slices out from the edge and often holes in the deflector itself.
So, if you see no opening in the deflector, this is an upright sprinkler.
If you see openings in the deflector, there are high chance that this is a pendent sprinkler.
But it may also be an old-type sprinkler, that can be installed in any position, upright or pendent.
The deflector of an old-style sprinkler is a mix between the upright and pendent shape. There are openings, but less than for a pendent sprinkler. And the deflector Is a curved shape. These ones are the most difficult to check visually, and in case of doubt, you need to see them closely.
Believe or not, there hasn’t been a single year where I personally haven’t found problems during these visual inspections with sprinklers installed in the wrong position. It is not uncommon to find an upright sprinkler installed in the pendent position and vice versa.
Reasons are multiple. One can be the lack of knowledge of the contractor and he takes the one he has in the box and installs it… as long as the thread is fine, it should be fine.
Another one can be after damages on a sprinkler, or a small fire controlled by one or two sprinklers. Someone onsite assumes there is no need to ask a contractor to replace them, you just need to take one of the spare sprinklers that are available in the spare sprinkler box.
And… we know if you have a 50% chance to take the wrong one, you will pick up the wrong one every time (this is Murphy’s law!).
I’m Franck Orset, this is MeyerFire University.
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