An April 2008 investigative report in the Sacramento
(Calif.) Bee has brought to a rolling boil the long-simmering
dispute between the building industry and safety experts over
contact-triggered (or “bump-fired”) pneumatic
nailers.
While some might fault the report’s tone as overly
sensational — a good part of it dwells on graphic
descriptions of injuries and interviews with family members of
fatally injured workers — it raises a question that
can’t easily be dismissed: Is the speed and
convenience allegedly gained by using contact-triggered nailing
worth the tens of thousands of injuries — and at least
a few deaths — that it causes each year? (The Bee
story is posted online at
www.sacbee.com/health/story/850428.html.)
Crunching the numbers. Duke
University researcher Hester Lipscomb has been tracking
pneumatic nailer use and associated rates of injury for more
than a decade, and was among the experts cited by the newspaper
story. During an interview with JLC, she confirmed the
Bee’s report of 42,000 nailer injuries per year, a
figure she attributes to a study published in the public-health
journal Morbidity and Mortality Weekly Report in 2007.
That number — 42,000 — was recorded at the
height of the recent construction boom in 2005; the annual
average during the five-year study came in somewhat lower, at
37,000 injuries. However, these figures cover only those
injuries that led to an emergency-room visit; according to
Lipscomb, the total number of injuries — many of which
are self-treated — is certainly much higher.
The Bee story also reported Lipscomb’s finding that
workers using contact-triggered tools have an injury rate twice
that of workers using sequentially triggered tools, which
require the operator to manually activate the trigger for each
fastener. And that’s actually a best-case scenario:
Lipscomb told JLC that this doubling of injury rates with
contact-fired nailers is typical among experienced,
well-trained workers. When inexperienced and poorly trained
— or untrained — workers are considered as
well, injury rates climb even higher.
Other research Lipscomb has conducted reaches similar
conclusions about the dangers of bump-nailing. In 2003 she and
three co-authors published a report based on a multiyear study
of actual accident rates among hundreds of residential
carpenters in the St. Louis area. The authors estimated that 65
percent of the injuries incurred while using contact-trip
nailers could have been prevented if sequential firing had been
used instead. Yet another study — this one among
carpenters in Ohio and North Carolina — concluded that
69 percent of nailer injuries could be attributed to
inadvertent nailer discharge or misfire; both problems can be
largely eliminated by using sequential triggers.
Interestingly, the St. Louis study also showed that 70 percent
of the studied injuries were associated with tasks typical of
framing — rather than with flat-nailing jobs like
sheathing — so it’s possible regulatory
agencies would deem bump-nailing acceptably safe for some
applications even if sequential-trip nailers are mandated for
framing.
Just a matter of time. In 2002,
pneumatic tool manufacturers responded to growing safety
concerns by adopting ANSI standard SNT-101-2002, under which
they voluntarily ship tools from the factory in
sequential-trigger mode.
Most of these tools, however, are designed to be —
and almost always are — converted to contact
triggering by the user, either with an easily installed
conversion kit or by flipping a selector switch. Given the
continued high injury rate since the adoption of the standard,
some industry insiders concede that an outright ban on
contact-triggered nailers may be inevitable.
“I believe it’s coming,” says Chris
Dutra, vice president for product development at
Stanley-Bostitch. “Whether it’s next year or
in two or three years, it’s probably just a matter of
time.”
Such regulation, in Dutra’s view, won’t
necessarily have a major impact on the industry. “If
regulators tell everyone they have to go with sequential
triggers, we’ll just do it,” he says.
“It’s really not an issue as long as
there’s a level playing field.”
But Dutra dismisses out of hand one contention made in the Bee
report: that manufacturers prefer to sell contact-triggered
tools because they use more nails. “That’s
ridiculous,” he says. “As someone
who’s been involved in product development for years,
I can tell you that’s never, ever even been
discussed.”
More to come. One question not addressed by the
Sacramento Bee — but of great interest to
those in the building trades — is whether a wholesale
shift to sequential-fire tools would overwork trigger fingers
enough to cause an upsurge in repetitive-motion injuries.
Lipscomb, for one, doesn’t expect that to happen. She
notes that the St. Louis study — which examined every
injury associated with nailer use, not just puncture wounds
— found only two cases of repetitive-motion injury.
(One worker also suffered a back injury from picking up a
nailer.) And even if increased use of sequential-trip nailers
did lead to more such injuries in the future, she argues, the
overall injury picture would be far less dire than it is today,
and any problems that did emerge could be corrected with
better-designed triggers.
Also unknown is what effect a phase-out of contact-trip
nailers would have on productivity. Although many builders are
convinced that contact-trigger tools are substantially more
efficient than sequential-trigger guns, there’s little
solid data to back that assumption up. It’s a void
Lipscomb’s team plans to begin filling with a new
study slated to be released this summer. Stay tuned for more
information. — Jon Vara
Offcuts
For the first time in its history, building-materials giant
Home Depot has announced the closure of selected flagship
stores for poor performance. Over half the 15 stores slated to
close are located in the central states: three in Wisconsin,
two each in Ohio and Indiana, and one each in Kentucky,
Minnesota, and North Dakota. The others are in Louisiana, New
Jersey, New York, and Vermont. Even after the closures, the
company will operate more than 2,200 stores in the U.S.,
Canada, Mexico, and China.
In response to what it calls “a small number of
Tacoma vehicles exhibiting excessive corrosion of the
frame,” Toyota is offering to buy back models sold
from 1995 to 2000. The company will pay one-and-a-half times
the Kelley Blue Book “excellent condition”
value to owners of pickups with frame damage too serious to
repair, and has extended the original warranties of all listed
trucks from three years and 36,000 miles to 15 years and
unlimited mileage. The program covers an estimated 813,000
trucks and is expected to cost the manufacturer up to $100
million. For details, including information on how to schedule
a free frame inspection, call Toyota at 800/331-4331.
A recently released NAHB 2008–2009 national
housing-start forecast contains the usual helping of bad news
that builders have come to expect in the past year or so, but
it also holds out some hope for a turnaround — in some
areas, at least — by next year. The NAHB expects
housing markets in the Northeast and South — excluding
Florida — to recover sooner than those in the Midwest;
markets in California, Phoenix and Las Vegas will lag
behind.
Broken Compact Fluorescents: Handle With Care
What’s a conscientious builder to do? Because
compact fluorescent lamps (CFLs) are so much more
energy-efficient than ordinary incandescents, using them helps
reduce the coal-fired power-plant emissions that are a
significant source of toxic mercury in the environment. Yet
CFLs themselves contain mercury: When a bulb is broken, the
mercury is released, creating a potential indoor health hazard.
It’s an issue builders can expect to hear about from
their clients as CFLs become increasingly popular.
As it happens, two recent reports — one from the
Vermont-based Mercury Policy Project and the other from the
Maine Department of Environmental Protection — offer
some perspective on the mercury threat, as well as guidelines
on how to clean up broken bulbs. Neither recommends that
consumers stop using CFLs — only that their use be
avoided in certain applications, such as in easily overturned
lamps in a child’s room.
Both reports conclude that a single broken CFL can release
enough vaporized mercury to create a short-term spike in the
indoor mercury level. The increase is significant enough to be
cause for concern. The federal Agency for Toxic Substances and
Disease Registry, for example, sets the maximum safe
“reoccupancy level” — the point at
which it’s safe to move back into a
mercury-contaminated building that’s been
decontaminated — at 1,000 nanograms of mercury per
cubic meter of air. (One nanogram is equal to one billionth of
a gram.)
Tests performed by the Maine DEP found that indoor levels
could briefly rise to as high as 100,000 nanograms of mercury
per cubic meter of air immediately after a lamp was broken. In
one case, a Maine field inspector measured a level of nearly
2,000 nanograms of mercury per cubic meter of air directly
above the spot where a lamp had broken on a carpet several days
earlier.
However, the two studies also found that the airborne mercury
levels quickly fall to near-background levels once a space has
been ventilated to the outdoors. It’s best to take a
common-sense approach to dealing with a broken bulb:
Immediately open a window to allow the vaporized mercury to
escape and — if possible — close the door to
the room where the break occurred. Once the space has
ventilated for 30 minutes, carefully pick up the larger
fragments and put them in a glass jar; use duct tape to lift
chips and dust and then place it, too, in the jar. Seal the jar
tightly for disposal. (State laws on disposal of broken
fluorescents vary. Some require that they be handled as
household hazardous waste, while others consider them regular
trash.)
Both studies caution against sweeping or vacuuming the area,
which can spread particles of mercury over a wide area.
According to Maine DEP’s Stacey Ladner, bulbs that
have broken on a carpeted surface are especially problematic
because they’re very difficult to clean thoroughly. If
children or pregnant women live in the house, Ladner says it
may be worth cutting out a dinner-plate–sized piece of
carpeting at the site of the break to prevent any retained
mercury from becoming airborne later.
To read the reports, go to
www.jlconline.com/maine
and
www.jlconline.com/mercury.
— J.V.
Go Green, Big Builder
According to a recent study by the Calvert Group, a
Maryland-based investment management firm, the
nation’s largest home builders — already
reeling from falling home prices and a critical shortage of
buyers — now have something else to worry about:
They’re falling behind smaller, more responsive
companies in the fast-growing area of green and sustainable
building.
“We believe that if these companies wish to continue
as market leaders in new residential construction,”
the study’s authors wrote of large, publicly traded
home builders, “they should embrace the opportunity to
drive the market toward more green building. If they do not,
they face the risk that smaller companies will surpass them in
meeting this growing area of consumer demand.”
The study also ranked the country’s 13 biggest
builders numerically according to their commitment to
sustainable environmental practices. KB Home tops the list,
followed by D.R. Horton and Pulte, which tie for second. NVR
comes in last, behind MDC Holdings and Standard Pacific.
To see the complete study, go to
www.calvert.com.
— J.V.
RECALL
DeWalt is recalling 13,000 of its DW744 portable 10-inch
table saws because of a defective pivot bracket that can allow
the blade and rip fence to misalign, possibly resulting in
kickback. The recalled saws were sold at home centers and
hardware stores nationwide from April 2007 through January of
this year. To see if your saw is affected, check the date code
on the nameplate located on the front of the tool; affected
models will have date codes ranging from 200715 to 200740. Saws
with an “X” stamped on the nameplate next to
the date code are not included in the recall. If your saw is
among those recalled, stop using it immediately and contact
DeWalt at 888/742-9178 to obtain a free replacement.