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."
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
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
"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."
HERE to post your comments about this topic.
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.
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