by Thom Zaremba, shareholder at Roetzel & Andress
In recent blogs, we looked at how glass is recycled into everything from highway paint to rebuilt marshlands. We looked at how the Department of Energy uses the process of vitrification to convert nuclear waste into glass. We also looked at how bullet-resistant glass standards work and how they can be used to keep building occupants safe from armed intruders.
But what about fire? Can glass keep occupants safe when a building is on fire? Yes, it can! It’s called “passive fire protection.” But is passive fire protection really “passive”?
Sometimes we don’t say what we mean, and sometimes the construction industry picks some puzzling words to describe things. For example, we often hear about “opening protectives.”
Seriously?
What does that mean?
“Opening protectives” are simply fire-rated windows or fire-rated doors used to protect openings in fire-resistance-rated walls. You could ask why they’re called that, but the answer would likely be, “because that’s what we call them.”
So, what about “passive” fire protection? In the construction industry, “passive fire protection” means the parts of a building, such as windows, doors, walls and ceilings or floors, are constructed from fire-rated materials that don’t need human intervention or technology to activate their fire protection features.
Great! But, if a building is constructed with an “active” fire protection system, such as sprinklers, it doesn’t really need any “passive” fire protection to make it safe, does it?
Yes, it does.
Why? Because passive fire protection is built right into the doors, windows, walls and other parts of the building itself. If someone inadvertently turns the valve to the water supply off, which can happen, the building’s sprinklers may not operate. Even if the sprinklers do operate, they are only designed to slow or stop the growth of fires, not to put them out.
That means, whether a sprinkler system operates properly or not, building occupants still need to get out of the building quickly. That’s where “passive fire protection” automatically kicks in without the need for human or technological intervention.
The fire-rated glass and other materials used to construct fire walls, fire windows and fire doors are all tested by certified third-party laboratories to ensure that they will stop fire, smoke and hot gases for 20 minutes up to several hours. Some fire-rated glass is even designed and constructed to stop the heat of a fire from passing through it, just like other opaque fire-resistant wall materials.
The “passive” use of fire-rated glazing results in the compartmentalization of buildings, that is, it separates one part of a building from others. When properly designed and constructed, these fire-rated compartments ensure that a fire in one part will not spread to others, giving its occupants the time necessary to evacuate.
The beauty of “passive fire protection” is that it is a silent part of the building. It will serve as a door, a window or a wall in the building, all while automatically standing ready to provide its building occupants with safety from fire throughout the entire useful life of the building.
None of this is to suggest that there’s anything wrong with sprinklers or other active fire suppression systems. They prevent damage and save lives, too. In fact, the safest buildings are those designed with a combination of passive and active fire protection features and systems.
In my next blogs, we’ll explore a variety of subjects, such as:
- Where passive fire protection features can be found in buildings;
- Why buildings need to use all available passive and active fire protection features to protect their occupants;
- How the increase in battery-operated electronics and vehicles, big and small, can increase the fire risk to building occupants; and
- How fire-rated glass can protect building occupants from multiple risks, such as fire and active shooters.
Please stay tuned!