READER QUESTION:
Regarding the Roco video/technique for shortening webbing... what is the strength impact on the webbing with this technique? When going from the looping double/basket method to a choker configuration changes the strength quite a bit because of all sorts of twists and bends... would the strength impact be 50%?

ROCO TECH PANEL RESPONSE:
After reviewing your question, we decided to do some “in-house” testing. Of course, it’s unofficial, but here’s what we did and the results are shown below.

Using new 1-inch tubular webbing anchored to a fixed anchor 2 inches in diameter, a “webbing shortening technique” knot was placed in the webbing. The webbing was marked with a felt tip marker on both sides of the knot to measure slippage. A carabiner was placed in the test webbing and attached to the dynamometer by a short piece of 1-inch tubular webbing that was looped, doubled and ran through the attachment opening on the dynamometer. The dynamometer was then anchored to the load.

Unofficial In-House Test Results:

1. Unloaded 20-ft of 1-ft piece of tubular webbing:
   Force applied 3,340 lbf with 2½ inches of slippage in the webbing.
2. Loaded 30-ft webbing of 1-ft piece of tubular webbing:
   Force applied 3,560 lbf with ¾ inch slippage.
3. Loaded 30-ft webbing of 1-ft piece of tubular webbing:
   Force applied 5,080 lbf with 1 inch slippage.
4. Loaded 30-ft webbing of 1-ft piece of tubular webbing:
   Force applied 5,460 lbf with 1 inch slippage.
5. Loaded 40-ft webbing of 1-ft piece of tubular webbing:
   Force applied 5,620 lbf with ¾ inch slippage.
6. Loaded 40-ft webbing of 1-ft piece of tubular webbing:
   Force applied 6,230 lbf with 1 inch slippage.

Tests #1 & #2 were slow tension pulls on the knot. Tests #3 & #6 were dynamic shock loading. Tests #5 & #6 both had failures of the 1-inch tubular webbing anchor at the attachment to the dynamometer. The failed anchor webbing was in a basket looped and doubled configuration and failed at the sharp angle connection on the device.
The test webbing did not fail in any of the tests, but on tests #5 & #6 it showed slight glazing on the inside of the knot when inspected.

Due to the failure of the anchor webbings, we were not able to generate more than the 6,230 lbf force on the system. Based on these unofficial tests, I would feel comfortable using the technique for NFPA General Use loads and would not expect it to weaken the webbing any more than the efficiency loss of any other knot that would be tied into the webbing, including a water knot.

NOTICE: The information provided on our website and by our Tech Panel is a complimentary service for our readers. Responses are based on our understanding of the reader’s inquiry, the equipment and/or the technique in question. All rescue systems should be evaluated by a competent person before use in the support of any human loads. Proper training is required prior to use of rescue techniques or systems discussed. Because standards and regulations are typically performance based and often dependent on specific circumstances, it is important to review all regulations in their entirety and to follow the proper protocols for your company or organization.

 

QUESTION FROM OUR READER:
In the new Stokes lashing video the instructor tied 2 butterfly knots into the webbing. Can this also be done with 2 figure eight knots in the webbing? Also I was looking for the information on Sked lashing, with by-passing the top 2 grommets and starting with the first 2 on the sides.

ANSWER:

The answer to your question about substituting figure-8 knots for butterfly knots in the webbing for the stokes lashing is Yes you can. You could also use two separate pieces of webbing to accomplish the same goal. Check out our Skedco Alternate Lashing Guide for details.

Here's a question for the Roco Tech Panel from one of our readers.
I recently became the ERT trainer. I have introduced the Petzl descender to the group and they love it. The question was brought up about the rating for lowering and raising of patients. What is it limits and can it be used in hauling up a two-person load? The max load the manufacturer says is around 600 pounds, and I am not sure if this is enough to meet what NFPA says. I really enjoyed the video Roco put out on this device, and would really enjoy seeing more on on other equipment.

Answer from the Tech Panel: Yes, you can use the Petzl ID-L (ID with red side plates that is NFPA G-rated) for raising and lowering two-person loads. For the ID-L, 600 lbf. is the “design load-rating requirement” for NFPA 1983 General Use. There are also two other ID versions – one with a yellow/gold side plate (ID-S) that is designed for smaller diameter ropes; and a blue side plate version, which will handle ½” rope like the red side plate but with a 550 lbf. design load.

So, what is the design load? Typically, it is the amount of weight/force a device or a system can handle; or the load that it is designed to handle. Once it has met the design load requirement for NFPA, it is placed in an equipment category and tested accordingly. In the case of the ID, it is tested as a descent control device. According to NFPA, General Use descent control devices shall withstand a minimum test load of at least 22 k/N (4946 lbf) without failure. I know what you’re thinking, “Hey, that’s not anywhere near the 9000 lbf we’re used to hearing for General Use?” NFPA requires that rope and carabiners be rated at 8992 lbf with pulleys and some other auxiliary items at 8093 lbf. Rope grab device shall withstand a minimum test load of at least 11 k/N (2473 lbf) without sustaining permanent damage to the device or rope to meet General Use. So, there is a wide range of strength requirements in NFPA 1983 depending on what category an item is tested in.

You must also consider that NFPA 1983 is a manufacturer’s standard and provides strength requirements for equipment to be classified as (T)-Technical Use (300lbf working load) – or (G)-General Use (600lbf working load). Rescuers must also refer to the manufacturer’s recommendations for use. However, an NFPA 1983 G-rating provides a quick field reference to the working load and confirms that a piece of equipment has been tested accordingly. This is important because OSHA will most likely look at this if there is an incident.

To answer your question, the manufacturer (Petzl) allows the ID to be used for the lowering and raising of two-person loads. If you have any other questions or need more information, please let us know – we’ll be glad to help. Check out our latest additions to our Video Resources for other great information!

Report submitted by John Voinche', Sr. Vice President/COO, Roco Rescue

In July, a group of Roco instructors conducted a Confined Space Rope Rescue demonstration for OSHA representatives from Washington, DC. These agency officials represented both General Industry and Construction. This demo was used to clarify our concerns about a pending Letter of Interpretation (LOI) concerning Individual Retrieval Lines in confined spaces that was brought to our attention last year. Here is a little background…

Last July (2011), we brought you a story entitled, “What’s the talk about individual retrieval lines?”  At the heart of the issue was a pending LOI from OSHA regarding how retrieval lines are used inside confined spaces. [Note: This LOI is pending and has not been published in the Federal Register.]

Here’s the question to OSHA from a gentleman in Maryland which initiated the LOI…

“Does OSHA 1910-146 (k)(3) require that each individual entrant, including workers and/or rescuers, entering into a confined space be provided with an independent retrieval line or can more than one entrant be connected to a single retrieval line?”

The proposed answer from OSHA stated that each entrant should have an “individual” retrieval line, despite the fact that the word “individual” is not included in this section of the standard [1910.146 (k)(3)(i)].
 
Roco then wrote a letter to OSHA requesting clarification about the forthcoming LOI. A portion of our letter stated that, “This pending interpretation is different from our understanding of what’s required by the regulation. While this particular technique is one option of providing external retrieval, there are other alternatives currently being used by rescuers.”


One of the techniques being used is a “single retrieval line” for multiple entrant rescuers. The first rescuer to enter the space is attached to the retrieval line via an end-of-line Figure 8 on a Bight. Any subsequent rescuers enter the space attached to the same retrieval line using mid-line Butterfly knots. In our opinion, this satisfies the intent of the regulation in that each entrant is attached to a retrieval line.

However, in the case of multiple entrants, requiring “individual” lines as mentioned in the proposed LOI may represent an entanglement hazard. This, in effect, may cause entrants to opt out of using retrieval lines due to potential entanglement hazards (which is allowed by the standard if entanglement hazards are a concern). So, in our opinion, this effort to bring more clarity to the issue may further complicate the matter.
 
Again, we believe the single retrieval line method described above is one way to rescue entrants while satisfying the intent of the standard at the same time. More background is available by reading our original story.

Fast-forward back to July 2012… the demonstration lasted about four hours. During this time, Roco demonstrated numerous retrieval line techniques as well as the “pros and cons” for each system. There was a great deal of discussion back and forth on how this pending letter of interpretation could affect rescuers and entrants – and their ability to perform their jobs safely and efficiently.
 
We would like to thank OSHA for allowing us to offer our feedback concerning this topic. We also want to say a special thanks to the Baltimore Fire Department for allowing us to use their training facilities. We don’t know when a final LOI will be issued, but we will keep you posted!

QUESTION: What is required for making multiple confined space entries, and can an Attendant/Hole Watch monitor more than one entry at a time?

ANSWER: Good question! And, the answer is YES according to OSHA 1910.146. However, each space must be evaluated on its own merits with all regulations and requirements applying to each individual entry. Here we will provide some tips when considering one Attendant for multiple entries. This is also where preparing comprehensive rescue preplans becomes essential, and we'll start there.

Suggestions for Writing Rescue Preplans

1.  One of the first things is to identify and categorize the space as “permit-required” or “non-permit required.” You’ll need to carefully consider the possible hazards based on the information gathered.

2.  Once you’ve identified the hazards, you’ll want to consider what actions might be taken to eliminate or control the hazard to allow for a safe entry. OSHA 1910.146 defines "acceptable entry conditions" as the conditions that must exist in a permit space to allow entry and to ensure that employees involved with a permit-required confined space entry can safely enter into and work within the space.

3.  Next, you would need to consider the type of work that is going to take place inside the space. A very important question to ask... could the work create its own hazard? (An example would include hot work being performed inside the space.) Then, what about rescue capabilities and requirements? Next, you’ll need to determine whether the entry should be considered “Rescue Available” or “Rescue Stand-by?”

Roco uses the terms “Rescue Available” or “Rescue Stand-by” to better prepare for safe entry operations and in determining more specific rescue needs for that particular entry. Here’s the way we use these distinctions...Rescue Available would be your normal entry that is NOT considered an IDLH (Immediately Dangerous to Life and Health)entry. In this case, a 10-15 minute response time for a rescue team would generally be sufficient to satisfy OSHA regulations and is typical during turnarounds where multiple entries are taking place.

On the other hand, we use Rescue Stand-by when a more immediate need is anticipated, such as with a hazardous atmosphere or potentially hazardous atmosphere. For example, with an IDLH entry, it may require the team to be standing by just outside the space in order to reach the patient in a timely manner (i.e., how long can you live without air...3 to 4 minutes?)  Or, how quickly can the entrant be engulfed where there is a potential engulfment hazard?  OSHA 1910.134 requires a standby person or persons capable of immediate action with IDLH atmospheres. (See reference below.)

OSHA Reference Note to Paragraph (k)(1)(i): What will be considered timely will vary according to the specific hazards involved in each entry. For example, §1910.134, Respiratory Protection, requires that employers provide a standby person or persons capable of immediate action to rescue employee(s) wearing respiratory protection while in work areas defined as IDLH atmospheres.

Regarding multiple entries, this Rescue Stand-by status could certainly limit the number of entries that could take place due to the availability of qualified responders and equipment. You must also consider that if you’re doing an entry that requires Rescue Stand-by and are called to respond to a rescue from a Rescue Available space, the entrants at the Rescue Stand-by entry must be evacuated before the team can respond. And, if there is only one rescue team, all other entries must stop during a rescue, as the team is no longer available.
Can an Attendant cover more than one confined space entry at the same time?

According to OSHA (see below), attendants can cover multiple spaces as long as they meet the responsibilities and duties at each entry site. If the spaces are “Rescue Available” and are in close proximity, this may be possible. However, without seeing the spaces and if they are on different levels as you mentioned, it could be very difficult for an Attendant to meet all of the requirements OSHA defines for Attendants.

OSHA Notes regarding Attendants and Multiple Entries...
NOTE to 1910.146(d)(6): Attendants may be assigned to monitor more than one permit space provided the duties described in paragraph (i) of this section can be effectively performed for each permit space that is monitored. Likewise, attendants may be stationed at any location outside the permit space to be monitored as long as the duties described in paragraph (i) of this section can be effectively performed for each permit space that is monitored.

1910.146(d)(7) If multiple spaces are to be monitored by a single attendant, include in the permit program the means and procedures to enable the attendant to respond to an emergency affecting one or more of the permit spaces being monitored without distraction from the attendant's responsibilities under paragraph (i) of this section;

Once all these critical factors have been reviewed, you will need to consider the following when writing a rescue plan for an identical space:

    Internal configuration
    Elevation
    Portal Size

For hazards and LOTO procedures, you may be able to use the same rescue plan to cover those spaces. An example would be in doing ten (10) ground-level entries into 6-ft deep manholes, each with a 24” round, horizontal portal with a valve at the bottom. The rescue plan may be identical for all of these entries with the same description and hazards. However, on the rescue plan, you would need to allow for any unexpected hazards such as a possible change in atmosphere. This would be needed to be detected and properly handled by the responders at the time of the incident.

So, these are some of the basics you need to consider when writing a rescue preplan for confined spaces and for determining if (and when) an Attendant can effectively monitor multiple spaces.

If you have questions concerning these topics, please feel free to contact Roco at 800-647-7626.