[RE-wrenches] Roof anchors and proper rigging

Glenn Burt glenn.burt at glbcc.com
Fri Apr 23 16:08:06 PDT 2010


So many points to consider here


 

OSHA does not recognize any ‘climbing gear’ as suitable for fall protection
in construction of any kind, so be careful #1.

 

I have been rock and ice climbing since the 70’s and would like to add a
couple of more caveats, or points to ponder to this discussion. Climbing
rope is also called kernmantle. This means there is a sheath woven around
the primary nylon core that is the true protection when falling. It is made
this way for better handling characteristics during climbing which is an up
and down and across rock outcroppings, dragging across obstacles, and
becoming more heavy to pull against as you move upward away from the belay
point. Also it uses carabiners and other fixed points of protection
installed along the way, creating small radius bends when a fall occurs.
These additional parts (carabiners) are designed to be lightweight aluminum
alloys, tested for strength in both dimensions, and rated with their load
bearing values. Again OSHA does not recognize these as suitable for fall
protection. The only approved ‘biners I have seen are steel, please don’t
confuse the two, as it is possible to saw through an Al biner over time with
heavy use


 

Being a nylon rope, it is easily damaged by chemicals, repeated falls or
heavy loads, as well as UV from sunlight. Due to its construction it is
impossible to determine when the core of the rope is damaged. This is the
source of climbers going ballistic when someone steps on the rope on the
ground – dirt and grit is driven into the sheath and core of the rope, where
it begins cutting the ‘kern’, unseen. Climbing rope is also given a lifetime
in number of falls it has been rated to withstand and still deemed to be
safe – this number is quite small in relation to its cost, but is a fair
tradeoff for those whose life was saved by one.

 

Climbing rope is a dynamic rope. It is not meant to be used to hang on, its
purpose is to absorb the shock of a fall by dynamically stretching, as the
climber is connected directly to the rope, thus not breaking the spine.
Cavers use a static line that is designed to be hung on, and climbed
directly with proper tools. This type of rope is much closer to the rope
OSHA recognizes as suitable for fall protection than dynamic climbing rope.

 

Standard fall protection relies on a static laid (spiral wrapped and visible
for inspection) rope as the lifeline, and the shock absorbing protection is
provided by a separate device connected between the user and the rope,
usually a continuous length of nylon webbing folded back upon itself many
times and sewn together that will rip out the stitching at a tested force.
All parts of the approved fall protection chain are constructed so that they
are easily evaluated for damage with a visual inspection, and most
manufacturers provide small logs attached to their equipment for recording
who/when they were inspected for damage.

 

You can also buy mechanical automatically retracting fall protection (we
have switched our crews to these as we have become larger), that minimizes
the installer’s lines being stepped on or becoming macramé on the roof
during the install.

 

All anchors for fall protection need to be installed according to the
manufacturer’s instructions, using recommended anchor screws. Not what you
have on the truck, or what you saw someone else using. You are trusting your
life and possibly someone else’s on these fasteners – this is no place to
scrimp!

 

I highly recommend that at the very least you obtain a simple ‘roofers kit
in a can’ that is approved by OSHA. If you require the ability to hang from
your harness while performing work, many harnesses are available with
‘positioning loops’ built in for tying off to (as the primary point of
attachment for OSHA approved fall protection is high on the middle of the
back to keep someone hanging in free air upright).

 

Sorry for the soapbox
 but I teach PV nights at a local community college
and safety is a big part of what we need to promote and explain why it is
appropriate and when. It is a common misconception that rock gear is OK for
use in our industry, and as we grow and become more mainstream, we must
strive to be safe – after all we are combining two of the deadliest trades
when we are installing on a dwelling


 

Have a great weekend all!!

 

-Glenn Burt

 

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Rebecca
Lundberg
Sent: Thursday, April 22, 2010 9:17 PM
To: re-wrenches at lists.re-wrenches.org
Subject: Re: [RE-wrenches] Roof anchors and proper rigging

 

Hi Ryan,

A few thoughts on this. One, it is all about safety, and more than any code
or compliance concern, you should be concerned about the safety of you and
your crew, because that's basically why code is written. I spent 12-hours
today and 12-hours yesterday (who needs the gym?!) hanging from a 12:12
pitch roof to install solar modules on one of my job sites, and my roof
safety knowledge was put to the test because I had only 6" to work from on
the eave and side edges, so my entire roof safety was based on that roof
anchor and my gear -- there was no way to work in a safe way without it.

Roof anchors are not a big deal -- they are easy to install and easy to
remove and caulk with clear caulk so the attachment point is not visible
when you are done. How often does the homeowner inspect the roof peak for
goodness sakes? The caulk covering a roof anchor hole would never be visible
from anywhere, and if installed right a PV system should not require any
kind of maintenance outside of a rare module replacement or something.
Sometimes the roof pitch is shallow and perhaps a roof anchor per person is
not needed, but my job site this week required one roof anchor for each of
us -- your life is at stake here, it is important to understand the value
and limitations of these products. I have done PV installs on a standing
seam metal roof, and I would argue that a roof anchor installed permanently
(and painted) with the original installation on a metal roof is a VERY good
idea, because after-the-fact roof anchors are not feasible, and the chance
of needing to get up there sometime during the life of the roof is likely,
and NO travel on a steep pitch metal roof is safe without being anchored.
But putting a roof anchor on a residential roof after the fact is SO not a
big deal.

Attaching to the truck in the driveway might be a safe solution, but only IF
the angle of incidence is correct for your safety, i.e. only if the truck is
parked exactly opposite where you will be working on the roof. Also, it is
only safe until your partner needs to run an errand to pick something up and
forgets you are attached to it. Not really funny, I have heard REAL stories
of this happening to a colleague.....

Rather than a vehicle I prefer to use a sturdy tree on the opposite side of
the house if this is absolutely the best option and a possibility. For a
temporary scenario, i.e. a site assessment on a steep roof or on any icy
roof in winter, I use my partner as a safety belay on the north side of the
house. Yes, we throw a climbing rope over the house and use tried and true
climbing gear, knots, communication protocol (with walkie-talkies), and
procedure to help us be safe. The person providing the belay needs to be
'sturdier' than the person on the roof, usually, unless they are also tied
off to a tree.

In short, two suggestions. Yes, take an OSHA course so you are fully
informed of the legal requirements and safety reasons for making sure of
roof safety. And, and just as important in my opinion, I'd suggest you hook
up with someone who can give you some real fixed-ropes climbing experience.
I'm not kidding, this is THE most valuable skill I have as a solar
installer. I've taught my subcontracted electricians about roof safety, and
ensured that my crew has the best oversight possible because I KNOW what it
takes. There is nothing akin to hanging off an exposed cliff, hundreds of
feet in the air, with nothing but you, your climbing gear, your climbing
harness, and your rope, to ensure your safety. This sort of scenario really
taught me how to evaluate my gear and various scenarios so that I will live
to see tomorrow and pursue my work towards a more sustainable lifestyle for
America. Fixed ropes climbing is also fun! My ascending/rappelling skills
are used weekly in my work as a residential solar installer, and a good
knowledge of safe knot options has been invaluable as-well. If you can't
find a climbing gym locally, find an adventure racing team (more here:
http://mandatorygear.com/index.php?option=com_content
<http://mandatorygear.com/index.php?option=com_content&task=view&id=14&Itemi
d=30> &task=view&id=14&Itemid=30) and ask them to spend a few hours training
you in -- I'm certain you'll gain some valuable skills from the effort.

Sincerely,
Rebecca Lundberg

NABCEP Certified Solar PV Installer ® 

Owner/CEO, Powerfully Green

Executive Board Member, Minnesota Renewable Energy Society

Convenor, Solar Minnesota

 

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