Fire Barriers are a first line of defense

Any sort of structure fire is a nightmare scenario, and there is always the risk of death and injury. Evacuations have attendant risks, too, especially when they happen in inclement weather. The need to compartmentalize fire and smoke to reduce harm, and allow for an orderly evacuation of occupants means having a plan in place. In addition, expansion joint fire barriers are a critical line of defense, and we offer eight keys to make sure those fire barriers are installed correctly.

A headline out of San Antonio was grim: Five die in senior living high-rise fire. The three-alarm blaze started on the third floor of an 11-story apartment building, and took 150 firefighters from 6 departments to control. Ten other residents were injured.

Evacuating residents in the late December chill was problematic as well.

And the following FEMA national estimates for non-residential building fires in 2012* adds to the grim picture:

• Fires: 92,800.
• Deaths: 65.
• Injuries: 1,450.
• Dollar loss: $2.5 billion 1

What is striking was that in a single year there were nearly 93,000 non-residential building fires.

This fire and others were mentioned in a recent article titled, “6 Layers of Defense Against Fires in Senior Living,” appearing in SeniorHousingNews.com.2 Among the layers of defense were:

• Install a sprinkler system
• Use non-combustible materials
• Upgrade kitchen cooktops
• Separate the laundry facilities
• Maintain fire-prevention and suppression systems

What caught our attention was one more layer – Construct smoke and fire barriers, which highlights the need to break a building into “compartments” to contain fire and smoke within the compartment and slow its spread.

“For nursing homes and higher-acuity assisted living [communities], it’s dangerous to evacuate residents outside in inclement weather,” said Mark Warrick, who leads the Austin, Texas-based firm Pi Architects. “It’s much safer to have a ‘defend in place’ methodology, and that’s where the smoke walls and fire walls come into play. You can take residents from one compartment to another and the fire and smoke are contained.”

We would like to extend this thinking in two ways:

1. Compartmentalization applies to more than senior housing, and all the defensive layers mentioned can apply to just about any facility.
2. It is important to dial expansion joint fire barriers into the lines of defense.

In 1980, 84 people died and 679 were injured as a result of a fire at the MGM Grand Hotel in Las Vegas.

One reason this fire spread rapidly from floor to floor was that there was limited fire protection at the expansion joints and other vertical shafts. This was insufficient in preventing the resulting “chimney effect.” Fires create tremendous pressure differentials between spaces — even through a hole as small as a pencil — once smoke finds a way through, air pressure quickly moves the smoke to fill the adjacent space. And it’s the smoke that kills.

Barriers also reduce temperature rise in adjacent areas to ensure occupants aren’t asphyxiated as they pass through a space.

The MGM tragedy as well as a theater fire in San Francisco shortly thereafter initiated the complete revamp of the Fire code that has resulted in the NFPA requirements we are familiar with today. Bottom line: expansion joint fire barriers can save lives and reduce the risk of injuries.

Fire barriers not only stop actual flames, but also compartmentalize the smoke and noxious chemicals they carry with them. When specified and installed properly, fire barriers help prevent fire and smoke from penetrating an expansion joint opening for a specified amount of time, called the rating period.

In all cases, the fire barrier is designed to prevent the temperature on the cold side of an expansion joint opening from rising above a predetermined rate for the specified rating period. The cold side of an expansion joint opening refers to the area within a structure adjacent to or opposite the surface where a fire or smoke source is located.

Mineral Wool and Sealant

Usually in two forms that offer a cost-effective and non-invasive anchoring through the compression.

Fire Stop

Open-cell polyurethane impregnated with a fire-retardant material – features a finished silicone face and addresses joint movement, acoustic dampening and insulating needs.

Fire-rated Foam

Open-cell polyurethane impregnated with a fire-retardant material – features a finished silicone face and addresses joint movement, acoustic dampening and insulating needs.

Fire Blankets

Encapsulated or non-encapsulated ceramic cloth, intumescent layering, graphite sheet goods or insulating blankets with galvanized flanges mechanically anchored to the substrate.

• Addresses seismic movement for joints 2-32”
• Must be capable of lateral shear up to 50% of the gap width.

• The barrier system must be tested to meet a particular rating (in hours) per UL and ASTM standards.
• The tests must be executed by an authorized third-party testing organization.
• The entire joint system is what must be tested and rated, not just the fire barrier material – meaning:
  • The floor or wall assembly,
  • The expansion joint cover system: frame, cover and hardware, AND
  • The fire barrier within the joint

One more thing: Manufacturers must sell the exact expansion system that was tested in order for the fire rating to apply. Any substitutions or changes could void the rating.

There are three areas where expansion joint fire barriers in a building’s design can go wrong:

1. There are design or detailing errors.
2. The incorrect system is specified.
3. Numerous failure points creep in during installation.

• Poorly installed transitions
• Parts Missing
• Air Gaps
• A wet blanket

1. A good substrate – a fire rating is only as good as the rated construction around the barrier.
2. The fire barrier is a continuation of the rated construction.
3. Consider the fire barrier as a complete system: Frames, splices, transitions
4. Expansion joint covers – or lack thereof – are part of the testing of the fire barrier. (Remember, the entire expansion joint is tested by the third-party certifying (testing) organization.
5. Ability to meet field conditions – sometimes the construction process throws a curve. The expansion joint and barrier system should be able to “flex” to meet the demand and not void the fire rating.
6. Architects should inspect test documents or request test data when writing specs.
7. Architects should provide separate details for rated conditions instead of putting a note saying “Fire Barrier as or where required”. The contractor is going to build the project based on the details provided.
8. Architects are hired to be the watchdog for the owner. There is a need to tighten specification language, for example, “...10% of all expansion joint system cover assemblies installed will be randomly pulled up and entire expansion joint system will be inspected.”

Expansion joint fire barriers are just as important as sprinklers and extinguishers, even more so as they help to compartmentalize fire and smoke. This reduces the risk of death and injury, either from the fire itself or in evacuating occupants in a fire emergency.

As we have shown, errors and mistakes can creep into the construction process leaving joint systems with little or no fire-barrier protection. Life safety demands attention to detail when designing, specifying, manufacturing and installing fire-rated expansion joints. Allowing lapses means you’re playing with fire.