SAFETY & SECURITY
Fire Protection: A Three-Layered Approach

When thinking about life and property safety during a fire, what comes to mind? Smoke alarms, sprinkler systems, and fire extinguishers? Although these systems are beneficial, they are not perfect. Human error, faulty wiring, failed water supplies and other factors can contribute to system failure. A thorough fire protection plan for educational and healthcare facilities should include three critical layers: detection, suppression, and building compartmentation. This article will discuss these three layers of protection as a balanced approach to fire safety, as well as the role of specialized materials such as fire-rated glazing for effective compartmentation.

Fire-rated building materials such as gypsum, concrete, firestop sealants, fire dampers and
fire-rated glass divide a building into contained spaces that can slow or stop fire and smoke from spreading.

Fire Protection: A Three-Layered Approach
• Detection: The first layer of fire protection comes from smoke and fire alarms that alert building occupants to the threat of a fire.

• Suppression: Strategically placed sprinklers and extinguishers can help slow or stop a fire from spreading. Such components are considered “active” because they must first be triggered before they offer protection.

• Building Compartmentation: Fire- and smoke-blocking materials such as masonry, gypsum or fire-rated glass divide a building into compartments. Such “passive” components provide around-the-clock protection and can help slow the spread of fire.

Detection and suppression methods alone are not sufficient to protect lives and property. For example, in recent years fire sprinklers have been the subject of extensive recalls. Compounding the problem, sprinklers and alarms can be inadvertently disconnected, damaged, corroded over time, or even painted over, rendering them unusable. Sprinklers also need to be checked regularly, but are often not on the building maintenance plan. There are too many variables in a real life fire to rely exclusively on detection and suppression systems.

Building compartmentation, on the other hand, provides a passive back up that supplements active systems. The National Fire Protection Association has found that lack of compartmentation and rapid fire development have been primary factors in numerous multiple-fatality fires. Fire-rated building materials such as gypsum, concrete, firestop sealants, fire dampers and fire-rated glass divide a building into contained  spaces that can slow or stop fire  and smoke from spreading. By blocking flames and smoke, comp artmentation materials provide time for occupants to exit the building, and for firefighters to arrive. This is especially important in medical and educational facilities since additional time may be needed to evacuate ill patients or young students.

Building codes often promote compartmentation by requiring the use of certain products that meet specific test criteria. These include glazing materials, fire-rated doors, and walls that must be independently tested to determine if they meet the fire-rated criteria and then receive a listing for the appropriate period of time they are rated to hold up in a fire.

Detection, suppression, and compartmentation work together to promote life and property safety. Eliminating any one of these three layers weakens the system of inter-connected elements in an effective fire protection plan.

Fire-Rated Glazing
Historically, building materials such as bricks and mortar or stone were used to block flames and smoke. These heavy materials provide a physical block to flames and shield non-burning parts from intense heat. Modern buildings are more open and feature thinner walls, floors and ceilings, as well as extensive glazing, and thus require specialty products and building practices to support compartmentation efforts.

One of these specialty products is firerated glazing. Ordinary glass cannot withstand the high temperatures generated from building fires, but sheets of ceramic and other specialty materials can be produced to look like ordinary glass and provide protection against flames and smoke. In locations where fire protection is required, fire-rated glazing can replace solid brick or concrete walls allowing natural daylight into areas of the building that were previously visually blocked by thicker building materials.

There is also a critical relationship between sprinklers and glass. Even when sprinklers work as intended, the right type of fire-rated glass is needed to withstand the shock of the cool water on the heated glass. If standard glass is impacted by cool water from a sprinkler or fire hose, the thermal shock can cause the glass to shatter and vacate the opening. The flames and smoke can then move to other parts of the building. Firerated glazing is required by code to withstand the impact and cooling of water in a hose stream test. As a result, the glass stays in place to block flames and smoke.

Types of Fire-Rated Glazing
For many years, the only fire-rated glazing option was polished wired glass. Institutional in appearance, wired glass offered little impact resistance and could only be used in small sized openings. Today, fire-rated glass ceramics allow large clear sheets of glass that can incorporate options such as high safety impact resistance, thermal performance for exterior use, or even decorative glass products. Such fire-rated ceramic glass offers greater design flexibility, with a range of make-ups that can provide many different performance characteristics.

Enhanced performance for fire-rated glass can be achieved with surfaceapplied fire-rated film or through a lamination process. Such glazing can meet the highest standard of impact safety for glass (Category II of the Consumer Product Safety Commission (CPSC) Safety Standard for Architectural Glazing Materials, U.S. Code of Federal Regulations, Title 16, Part 1201). Glazing that meets this standard is designed to safely withstand the impact of a fast moving, full-grown adult. This can be particularly important in hospital emergency rooms or in busy school hallways where people may come in direct contact with the glass.

Ceramic glass can be incorporated into insulated glass units (IGUs) combined with other types of glass including tempered, float, mirrored, tinted, or lowemissivity. These IGUs can provide energy efficiency along with fire-protection.

While fire-rated ceramic glass works well to block flames and smoke, it does not protect people and property against high heat. For exit corridors, critical care areas, and rooms with heat sensitive equipment such as computer labs and patient diagnostic and imaging, glass firewalls may be appropriate. Similar to a masonry wall, glass walls block the transfer of radiant heat during a fire. This category of glazing is tested to the same standards as solid walls, with fire ratings up to two hours and can be installed in floor-to-ceiling applications for extensive glazed areas.

Whichever type of fire-rated glazing is specified, it is important to ensure that it has passed all testing requirements, is set in a frame assembly with equivalent fireratings and is listed by a trusted thirdparty agency such as Underwriters Laboratories (UL).

Fire-Rated Glazing can be used for more than Fire-Protection
In recent years, the desire to build more open and energy efficient buildings has lead to the incorporation of daylighting techniques into modern design. In addition to energy savings, daylighting provides environments where patients heal faster and students perform better. A study focusing on daylighting in schools concluded that, “there is a valid and predictable effect of daylighting on student performance.” Specifically, “Students in classrooms with the most daylighting were found to have seven percent to 18 percent higher scores than those in rooms with the least.” Daylighting in Schools: An Investigation into the Relationship Between Daylighting and Human Performance, a 1998 study conducted on behalf of the California Board for Energy Efficiency Third Party Program by the Heschong Mahone Group.

Patients are also known to benefit from daylight in their recovery process. A 2004 Texas A&M University study indicates, “Patients in a room with higher daylighting levels had shorter stays than those with lower daylight levels.” Study of the Relationship between Patients’ Recovery and Indoor Daylight Environment of Patient Rooms in Healthcare Facilities 2004, Texas A&M, Joonho Choi and Liliana O. Beltran.

Fire-rated glazing allows daylight deep into areas of buildings that previously had to incorporate concrete blocks or other opaque building materials to comply with fire codes. Imagine medical labs, stairwells, corridors and computer labs bathed with natural light instead of being dark places lit from artificial light sources.

Sprinklers and other active fire protection systems save lives and protect property, but are most effective when used in conjunction with passive systems. Incorporating a combined fire-safety approach using compartmentation adds an extra layer of protection to allow students, patients and staff to safely exit a building during a fire while keeping critical and costly equipment protected from flames, smoke and heat. With life safety at stake, the balanced approach is worth the extra effort.

Jeff Razwick is the vice president of business development for Technical Glass Products (TGP), a supplier of specialty architectural glazing products and fire-rated glass and framing systems. He writes frequently about the design and specification of glazing systems for institutional and commercial buildings. www.fireglass.com • 800.426.0279