On backflow preventers

Depending on the water jurisdiction your fire sprinkler system may or may not have a backflow preventer.  There are good backflow installations and bad backflow installations.  Most common is a lack of a proper drain for the relief valves on RPZ type backflow preventers.

Backflow preventers have their issues....

Close up of RV leaking below

Below, a typical double check backflow on a fire line - Florida.

Flushing test cocks prior to testing - industry requirement, below

Shown below is an installation with inadequate access for maintenance.  Logo of installing firm has been redacted.

Control Valve Tamper - Missing

Auxiliary Valves

Examples of Aux Valve Installations.

Anti-Freeze Systems

Poor fire protection contractor practice is noted below.

Below is an anti-freeze fire sprinkler system - protecting combustible attic as well as main floors.  No signage is installed indicating it is an AF system.

RPZ Backflow Preventors, Anti-Freeze Fire Sprinkler Systems

Design/Install error below.  Missing drain for RPZ backflow relief valve.  Drain should be installed and piped to floor drain or outside the building.  Damage may result from flow from RPZ drain relief valve.

Sprinkler Coverage - Design/Install Error. Not a Deficiency

Another example, another location:

No heat bank for HSW heads.  Heads still having manufacturer shipping clips installed.  Large mall in Kuwait City.

Alarm Valve Found Off (Outside Closed Curb Box/Street Valve)

The system shown here was found off - that is the water supply was found off.  The water supply was turned off OUTSIDE and UPSTREAM of this riser at an outside curb box street valve [not shown] due to a previously reported and repaired street leak.  The curb box/street valve was never turned back on.  The pressure on the riser supply side gauge is zero but you will note the OS&Y control valve is open. Pressure remains on the upper system side pressure gauge due to trapped pressure above the alarm valve.

It is important to tag these systems out of service.

The riser is also missing control valve tamper switch or chain lock and a hydraulic calculation placard.  The water motor gong [not photographed] alarm line 1/4 turn ball valve should also be sealed open or electrically tamper protected.

Location: Qatar.

Another system off, Kuwait:

Alarm Valve Deficiencies

Combination of Issues

Busy Riser

A lot going on here.  A clear and clean design is appreciated.  (In case you are wondering, these risers have excess pressure pumps installed on them - Connecticut)

Abandoned Fire Sprinkler Pipe

Abandoned fire sprinkler pipe and systems should be tagged / marked out of service.

Below is an abandoned structure on a military base.  Signs should be installed indicating this:

Design/Install. Foam Proportioner Not Installed per Manufacturer Recommendations

Field Modified Concealed Cover Plate. Non-Standard Design/Install.

Note, fire sprinkler system activation time would be delayed, spray pattern development might not occur.  Performance of sprinkler system seriously degraded by this field modification.

PIV closed, handle missing

Design/Install. Sprinkler Installation.

Design/Install. Sprinkler Placement

Design/Install. Exterior Dry Pipe System.

Dry pipe system mounted on exterior of building, Maryland. This was a temporary emergency re-installation of a dry pipe system.  The structure's roof had collapsed due to high snow loads and owner needed to reoccupy structure immediately.  Installers re-installed system with a portion of the dry pipe system on exterior of structure [part of the roof is missing].

Do Not Hang Sprinkler Signage - Nice Example of What To Do