Subscribe to USGNN!

USGNN Original StoryShould An Impact Resistance Standard Cover All Skylights?

While ASTM's "Specification of Human Impact Criteria, with Procedure for Testing and Rating Plastic-Glazed Unit Skylights and Related Products used on Commercial Walkable Roofs for Fall-Through Resistance" is still in the early stages of development, some skylight manufacturers are concerned that the impact-resistance standard will cover all skylight products-both glass and plastic.

According to Nigel Ellis, Ph.D., president of Ellis Fall Safety Solutions in Wilmington, Del., and chair of the E06.51.25 task group working on the standard, the task group was formed "because the toll of occupational deaths is constant from year to year."

CLICK HERE to see United States Bureau of Labor Statistics's data on fatal falls through skylights and HERE for data on nonfatal falls.

"And," Ellis continues, "since the design of skylights is controllable by manufacturers, it seems that all skylights should be tested with a uniform test method. That includes glass, plastic and fiberglass panels."

According to Ellis, the Occupational Safety and Health Administration is interested in seeing one impact resistance test method for all types of skylights. Glass industry groups also are interested in developing safety standards, but feel it is too early in the development stage to consider whether a test should cover all types of skylights.

"The members of the American Architectural Manufacturers Association's (AAMA) Skylight Council fully embrace the concept of acknowledging all aspects of health, safety and welfare relating to their products," says Ken Brenden, technical standards manager for AAMA. "The members are receptive to standards being developed for impacting 'unit' skylights. However, more studies, market analysis and involvement by other associations are needed before human impact loading standards can be effectively developed for all skylights."

Some manufacturers feel that even at this early stage the standard development should look at glass and plastic skylights as two separate entities.

"Testing of any kind must address the difference in types of skylights and their construction techniques; acrylic bubble skylights and glazed aluminum frame skylights are two different products when it comes to use, safety and testing," says Melissa Rizzo, marketing supervisor of Solar Innovations Inc. in Myerstown, Pa.

Some skylight manufacturers question whether glass products should be the subject of a test method at all.

"I do not believe that there is any evidence at this time which indicates that glass skylights have been involved in any fall-throughs," notes Randy Heather, standard products manager at Naturalite Skylight Systems, a part of Oldcastle Glass in Santa Monica, Calif.

According to John Westerfield, who handles marketing and code compliance for CrystaLite Inc. (a manufacturer of glass and plastic skylights) in Everett, Wash., "Plastic domed skylights are typically installed on flat roofs where workers are more likely to be exposed to skylights where the already-established OSHA fall protection requirements may be overlooked. This is typical when a worker must access a flat or low-pitched roof to do a one- or two-day job post-construction. Glass skylights typically are installed on sloped roofs, in which case workers are more likely to follow OSHA requirements and are protected from all falls with a personal fall arrest system of some sort."

"I would think these plastic or bubble skylights are more susceptible," adds Ron Palombo, president of Acurlite Structural Skylights Inc. in Berwick, Pa. "I'm not saying they're not strong, because you can get these things with remarkable test performance capabilities, but unlike the properties and the rigidity of glass-laminated glass, tempered glass-I would think these bubbles or plastic skylights are more susceptible to movement, susceptible to deflection."

CLICK HERE to post your comments about this topic.

CLICK HERE to read ASTM's announcement about the new task group.

Be sure to look for more information on this topic in the May issue of USGlass magazine.

Need more info and analysis about the issues?
CLICK HERE to subscribe to USGlass magazine.