OSHA 1926 Subpart M - Fall Protection

[Deadblow]

Hello All,

I do have this posted in the OSHA section also, but noticed the last post there was 4 months ago.

I am working with a contractor to establish a fall protection system to be used during the demolition of a bridge. The bridge deck is only 10'-0" off the ground. The contractor wants to install a warning line 6'-0" from all unprotected edges. Anytime an individual is outside of the warning line, they will be required to wear a full body harness and an 8'-0" lanyard anchored to a concrete block positioned at least 8'-0" away from the unprotected edges, thus preventing the individual from ever experiencing a fall. When the worker needs to move, he/she will step back inside the warning line, unhook from the concrete block, wait for a hydraulic excavator to re-position the block, and then reattach to the block.

Does this sound like an acceptable plan for fall protection? I'm not sure that it is. If I am interpreting the OSHA regulations correctly, when the worker unhooks, they are not protected even though they are not between the warning line and an unprotected edge. If my interpretation is correct, than what is the purpose of a warning line?

Thank you for your help!

EIT

 

[TehMightyEngineer]

That's not my interpretation. See the definition of warning line:

"Warning line system means a barrier erected on a roof to warn employees that they are approaching an unprotected roof side or edge, and which designates an area in which roofing work may take place without the use of guardrail, body belt, or safety net systems to protect employees in the area."

Also, using a tethered fall protection system for that seems inefficient. Why can't they just construct a simple wood guardrail at the free edge? That's far more typical.

Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries

https://www.facebook.com/AmericanConcrete/

 

[Deadblow]

TME,

Thanks for the quick response. The contractor plans to install a wood guardrail as you suggest for the erection phase. During the demolition phase of the deck slab, the leading edge will constantly be moving and the workers will need to be at this leading edge. The contractor has also expressed that they do not want to have to use a monitor. What systems/techniques should be used to accomplish the demolition while following OSHA? We were hoping that by establishing a warning line (or control line), the only time an employee needed to be tethered is when he/she is outside that line. But when I read the definitions for warning line and control line, they don't match our logic. We are trying to follow 1926.501(b)(10) and utilize a "warning line system and personal fall arrest system". Help clarify for me how warning lines and or control lines are used and when an employee is tethered or not tethered when such systems are in use.

Thank you for your time!

EIT

 

[dhengr]

Deadblow:
Call your local OSHA office, they are generally helpful when you go to them for help before an accident or inspection. In recent years, I think they have been told to try to be more helpful in trying to further their cause and directives. Try talking with several different people in the office, some are more helpful and willing than others. They’ve seen a lot of different conditions, and while they won’t design your system for you, they may have some helpful ideas and they will help you with std. interpretations and what they will accept, and what they look for. You will have to explain your particular conditions in more detail than you have here, but its not like you will be able to do this work without the whole world seeing it. So, you’re really not hiding any secrets.

 

[Deadblow]

Thanks for the advice! I learned something new and I will give OSHA a call directly.

EIT

 

[chicopee]

During demolitions of decks on our federally funded bridge construction on interstate system, workers were attached by full body harnesses with shock absorber lanyards hooked to lifelines on stancions. We also had platform hooked to crane to capture concrete debris falling during jack hammering and this platform provided additional fall protection. Afterward, OSHA revised the fall protection standard but by that time, I was no longer involved with bridge demolition.

 

[Lomarandil]

Deadblow, what you are proposing is fairly typical.

In some cases, rather than anchoring to a deadman, our contractors will be tied off to fall protection anchors set directly into the deck. They can come back and use a hammer drill to set a new anchor for themselves rather than requiring an excavator. Something like this:

http://simplifiedsafety.com/store/f...ncrete-anchors/concrete-anchor-10k-or-5k.html

Given your low fall height, I agree that you want to prevent falls over the edge rather than protect against them. A retractable lanyard with a quick catch distance may be more practical for your workers than a fixed length line (since, as you said, the leading edge is always moving).

Don't quote me on this (I didn't check it), but my understanding without going back to OSHA is that warning line or not, if you are at least 6' from a leading edge, there's no requirement to tie off. The warning line is more or less a good practice to remind people when they are within 6'. Most of our contractors set them 20' back so they aren't constantly having to move it (and to keep city inspectors at a safer distance).

 

[Deadblow]

Here is an update on what I found:

Because this is a bridge and not a "roof", the warning line system is not acceptable. We will either need 100% tie-off or a guardrail system. Period!

Thank you for all the help!

EIT