Installing a top-notch suppression system and assuming it will activate early enough to extinguish or stop the spread of
fire is not the answer for eliminating fire rated doors and windows.
Since sprinklers are an “active” system, they require several steps to activate for them to work properly.
Sprinklers need to produce enough water pressure to activate, without this constant pressure they won’t activate.
Water pressure is only one of many such factors. Water supply can be accidentally turned off,
sprinkler heads can be accidentally painted over and if the system isn’t maintained the whole setup is useless.
Are you beginning to see the danger of relying exclusively on an active fire protection system?
Sprinklers can be reliable and have saved lives and property, however they should not be a
replacement for more "passive" systems such as fire rated glass that can provide a degree of fire
protection without depending on any outside factors.
Additionally, a sprinkler system only works when the water coats the entire glass surface consistently.
If blinds, décor, furniture or even doors that are left open stop the water protecting the glass, the entire system is useless.
Advocates of fixed window sprinkler systems suggest working around the problem by simply making a written requirement that blinds, and combustible items are far enough away from the glass, so they do not get in the way of the water from the sprinklers.
However, the likelihood of future building tenants abiding by such restrictions is rather slim. As you
can see, this approach attempts to provide an answer and ends up creating a new list of questions.
A much less complicated approach would be to specify appropriate fire rated glazing in the opening.
Again, the passive nature of fire rated glass avoids many of the complications that arise when dependence
on active systems is increased
If the sprinklers extinguish the fire, it won’t matter if glass breaks.
We have raised several potential red flags regarding sprinklers. But let us suppose for a moment that there
has been a fire and the sprinklers have worked exactly as intended. The fire is put out even before building
occupants have the chance to evacuate.
Would it really matter if the glass in some of the windows and doors had been broken in the process?
The answer is a definite yes. One of the primary concerns in extinguishing a fire is smoke, since most fire related
deaths are caused by smoke inhalation. Sprinklers create an enormous volume of smoke. If glass has broken,
the smoke will be free to travel throughout the building, which means it can still threaten life safety even after the fire is extinguished.
Fire rated glass is intended to inhibit not only the spread of flames, but smoke as well.