A Behind-the-Scenes Look at Your Fall Protection Equipment
Ensuring fall protection devices are properly tested gives worker confifidence and peace of mind
- By Marty Sharp
- Jul 12, 2007
YOU buy and use fall protection harnesses,
lanyards, rope grabs, lifelines,
retractables, and other equipment
every day. Each item is labeled,
ensuring that it conforms to ANSI specifications
and OSHA regulations. These
product certifications give you confidence
and peace of mind.
Everything about fall protection is significant.
Each year, injuries and deaths from
falls are among the highest among reported
accidents in U.S. workplaces. OSHA
reported 5,504 violations of the general
requirements for fall protection from Oct.
1, 2004 to Aug. 30, 2005; only scaffolding
and hazard communication ranked higher.
Reliable equipment in the hands of
trained personnel is the solution to this
problem. Fall protection manufacturers
make every effort to deliver quality equipment.
Let’s take a look behind the scenes
and at a personal experience.
Lesson Learned
When I was 17, I worked at a wire rope
shop. One of my responsibilities was
making hundreds and hundreds of slings
for a power plant.
They wanted these slings lot tested by
having one out of five pull-tested to 150
percent of its safe working load. I
thought this was entirely too time consuming.
After the pull test, it would leave
a kink in the eye. Because the tester was
in the back of the shop and no one was
watching me, I threw 10 at a time into
the pull tester just to kink the eye.
This went on for some time, until one
morning when I heard that there were
three fatalities over a sling failure. Later in
the day, I found out it was one of the slings
I had made. How horrible a feeling: I was
personally responsible, through carelessness,
for the deaths of three people.
The next morning, I found out the
whole truth: The sling I had made had not
failed because it was improperly made or
improperly tested, but because the safe
working load cards that the company had at
the time were misread. The cards had the
safe working load on one side and the tensile
strength on the other. The supervisor
had misread the card and used the tensile
strength as a safe working load. They were
using two of the wire slings that I made to
lift some rebar. The three men were
working nearby when one sling gave way
and the rebar slid, piercing all three men
and killing two of them instantly. The third
lived long enough to bleed to death before
they could cut him free.
It was a life-changing experience. After
that, every sling that was supposed to be
tested was tested.
Test, Test, and Test Again
All manufacturers test their fall protection
devices; it’s the law! ANSI Z359.1’s testing
section (4.3.3.2, Dynamic Performance
Testing) states, “The drop test structure,
test torso, test lanyard of 4 foot (1.2 m)
length, and quick release mechanism shall
be in accordance with 4.1.1, 4.1.3, 4.1.4 and
4.1.6, respectively. The harness shall be put
on the test torso and adjusted snugly as
though the torso were a person. Attach one
end of the test lanyard to the fall arrest
attachment element and the other end to
the anchorage on the test structure. Harnesses
which incorporate integral lanyards
must have such lanyards removed prior to
the dynamic test. Raise the test torso to a
level which will allow a 3.3 foot (1 m) free
fall upon release of the test torso. The torso
shall be lifted to a point no more than 12
inches (305 mm) horizontally from the
anchorage. Release the torso using the
quick release mechanism. After the drop, the torso is to remain suspended by the harness for a period of 5
minutes. During the post-fall suspension period, measure the angle
at rest. . . . The dynamic test is to be done twice, once ‘feet first’ and
once ‘head first.’ A new harness may be used for each test. After
each test, evaluate the harness according to 3.2.2.7.”
The drop tower is also essential in the dynamic performance
testing of energy-absorbing lanyards. Prior to the drop, the length
of the energy absorber is measured while under a tension of 10
pounds. The energy absorber is then attached to the harness on
the 220-pound test torso and dropped, allowing for a minimum
free fall of 6 feet. The maximum arrest force is recorded. While
suspended, the length of the energy absorber is measured and
recorded, and the elongation is calculated. The ANSI standard sets
forth permissible limits.
These tests are performed on site weekly using quantities as
required.
The vertical load tester is used to measure the breaking strength
of the hardware components. Samples are tested to destruction.
The horizontal tester allows us to perform testing using a system as
long as 120 feet. Testing is based on a simulated two-person drop.
Readings are relayed by load cell to a PC and viewed in our lab.
“Tonzilla,” a pull tester that has a 60-foot test bed and 500,000-
pound capacity, is integral to our testing. I believe I designed
“Tonzilla” to somehow make up for my lack of responsibility in the
process of testing slings 25 years ago. The new machine is equipped
with three surveillance cameras inside the test bed that can zoom in
close enough to see the actual serial number on a sling, bracket,
anchor, or other device being tested, and then pull back to witness
the test while a split screen displays the scale of the load cell.
The tests are displayed on two 50-foot flat panel monitors for
live viewing and can be digitally recorded. In the near future, we
are going to have this system linked to our Web site, enabling
inspectors to watch their test in real time from their own laptop.
One of the other advantages of having a camera system is that
during our monthly safety seminars, I invite a large crowd of people
to learn how wire rope slings and fall protection devices are used,
made, and properly inspected. The grand finale is always in the pull
tester’s control room. For a more dramatic effect, we placed microphones
inside the pull tester and installed surround sound in the
control room. A lot of times it’s interesting to watch people anticipating
the moment when the cable will snap, by hearing the individual
wires start to more rapidly ping closer together until the final,
dramatic explosion of 250,000 to 300,000 pounds of energy is
released all at once. I think this really gets across the point on how
dramatic a failure can be; I hope at least one or two people out of the
crowd can take away some information so they won’t make the same
mistake that supervisor made many years ago. They will understand
the difference between a safe working load and tensile strength.
Death on the Order Desk
As manufacturers, it’s critical that we ask our customer the right
questions. I recall a situation many years ago when we sold some
5/8” cable to a customer and later learned it was undersized for the
job, resulting in a failure and a fatality. Had we asked more questions
at the order desk, the tragedy would not have happened. I
have become a fanatic, insisting that our people ask about the customer’s
application before completing an order. Most of our customers
appreciate this extra thought and time. I believe and trust
that you do, too.
This article originally appeared in the July 2007 issue of Occupational Health & Safety.