A couple of history questions:

Where does the rule of thumb 250 pound per worker come from? I maintain it is from the old fixed length stage platforms like Louisville Ladder where a 2 man stage was 2 x 250 lb. workers = 500 lbs. and a 3 man stage was 750 lbs. Loads were positioned centrally 18 " off centerline.

Also, where does 5000 lb. lifeline anchor number come from?

The 250 pounds per worker: this is in old safety standards. The Z359 has upped its drop test from 220 lbs with rigid torso to 282 lbs based on a 1.1 factor of a solid test weight to a 310 lbs human body rather than 1.4 until 2008.

In the A14.3-2008 fixed ladder std: two persons (rescuer plus victim) amount to 250 x 2 = 500 lbs test weight (no shape) dropped 18.

The new Skylight standard for Human Impact is at 267 lbs with a conical (5.5 and 18 dia.) shape bag and sand or lead fill to drop 36 to simulate force on a plastic skylight. This based on 95% male 2004 DHHS vs 234 lbs in 1980. If they chose 97% it would be 287 lbs.

5000 lbs for an anchor came from 5400 lbs the strength of a ﾾ manila rope in 1971 which was downgraded a couple of year later by the Cordage Institute to 4800 lbs so the OSHA model jumped to ﾽ nylon instead of manila rope, and was rounded to 5000 lbs.

In the ladder world hasnt the highest load limit ladder jumped to 375 lbs for a 1AAA rating.

We are definetly headed upward for static force weight limits.

We recently were cited for working next to a bridge parapet wall that was 29 inches in height. OSHA cited us, violation of 29 CFR 1926.502(b)(1) failure to provide top edge height of top rails, or equivalent guardrails systems members, that were not 42 inches plus or minus above the walking working surface.

We have been working around these walls for several decades. Other Ohio bridge contractors have been working on bridges in Ohio that have parapet walls at the same height and never have been cited. I am looking for any information that you could provide for me in regard to this or any other similar circumstances.

The OSHA standard is 42" guardrail height in construction +/- 3" except proportionately higher for use of stilts near guardrails. Another standard is viable however that can be used is the 4/10/90 proposed OSHA general industry fall protection standard. That requirements option is minimum height 30" but the sum of the parapet height plus width is minimally 48".

Since you are a leading authority in fall protection, I thought the following interpretational ambiguity might be of interest to you. The passages below (extracted from design review meeting minutes) indicate the concern (Company names were removed so as not to violate anyone's privacy) By far, the most discussed item related to the difference between the industry and the Company Safety interpretation of OSHA and ANSI requirements for fall arrest system design. This interpretational difference basically comes down to one point of contention --- that being the context of the word "used" as it relate to "supervision" by a Qualified person. From OSHA: 1926.502(d)(8): Horizontal lifelines shall be designed, installed, and used, under the supervision of a qualified person, as part of a complete personal fall arrest system, which maintains a safety factor of at least two. 1926.502(d)(15): Anchorages used for attachment of personal fall arrest equipment shall be independent of any anchorage being used to support or suspend platforms and capable of supporting at least 5,000 pounds (22.2 kN) per employee attached, or shall be designed, installed, and used as follows: 1926.502(d)(15)(i): as part of a complete personal fall arrest system which maintains a safety factor of at least two; and 1926.502(d)(15)(ii): under the supervision of a qualified person. From ANSI A10.14: 4.3.3.10: Lifelines shall be designed, installed and used as part of a complete personal fall arrest system under the supervision of a qualified person maintaining a safety factor of a least two. Anchorages to which lifelines are attached shall be capable of supporting at least 5,000 pounds (2273 kg) per employee attached, or shall be designed, installed and used as part of a complete personal fall arrest system under the supervision of a qualified person maintaining a safety factor of a least two. Company Safety, after verbal communication with our Regional OSHA office, contends that if an engineer designs an anchorage point for less than 5,000 pounds, or a lifeline with a fall arrest load per person less than 5,000 pounds, then the fall arrest equipment can only be used if the qualified person/engineer that designed the equipment is at the fall arrest equipment site continuously during the times that the equipment is used (i.e., used under the supervision of a qualified person). Company Engineering, and others in the meeting, contends that "used under the supervision of a Qualified person" means the Qualified person determines the equipment and functional manner of use (or constraints of use) for the safety device. This information is passed to the users of the safety equipment via training and signage at the site. Therefore, when someone uses the safety equipment, they are using it under the conditions set forth by the Qualified person (i.e., under their supervision). Fall arrest engineering companies also share this interpretation. These companies regularly design fall arrest systems for actual fall arrest loads with a safety factor of two, and would not be able to economically provide fall arrest equipment design and installation if federal regulations required them to permanently man each equipment installation site with the qualified person that designed the fall arrest equipment. Any clarity you can provide will be appreciated. PS - I saw the following passage on a web site: It should be noted that ANSI A10.14, "American National Standard for Requirements for Safety Belts, Harnesses, Lanyards, Lifelines, and Drop Lines for Construction and Industrial Use" was administratively withdrawn by ANSI and is no longer a recognized standard. Does this mean that design documents should no longer refer to ANSI A10.14 as a design standard to be followed, until some point in time when another organization takes over control of A10.14 from the NSC?

Use ANSI Z359.0-.4 - 2007 Fall Protection Code. This is a comprehensive set of requirements to address work at height. The A10.32 was released approx. four years ago and a new revision is in debate currently to determine if all or parts of ANSI Z359 should be adopted. The aspect of control is different in construction and also the environment is all-weather and different structures and mobile cranes and aerial lifts. Nevertheles Z359 is so broad it can be useful in any environment.

I've been doing a lot of rope access work and have followed the IRATA methodology for a while. While working at a petro chemical plant I had a conversation with a plant operator, he talked about ASTM standards and fall protection, does that mean anything to you?

The ASTM F13 Standards Committee handles slip resistance requirements for individual industries and various slipmeters. Industry is handled by ANSI A1264.1 & 2.

UK (Europe) follow IRATA's procedures and level.

Fall Protection in the USA is OSHA 1910 or 1926. ANSI Z359.1 and A10.32 are general industry and construction respectively. It is better, I think, to follow the strongest standard in which case 1926.500 series is far superior regarding fall protection than 1910 (except 1910.66 building exterior maintenance). SPRAT is the American equivalent of a rope access standard.

Are letters interpretation letters enforceable when used by a CSHO?

Interpretation letters are to be used for guidance only to employers and CHSO's; no new regulatory requirements are added in an interpretation geared to a hypothetical situation. There are no definitive general rule answers in interpretations.

Under Texas Gross Negligence - who is liable for injuries to an employee at work?

The statutory employer is liable when the employee is killed at work. Only then can this standard be applied against the employer.

Can you please tell me what is the Fed OSHA requirement for fall protection when working over water-with sufficient draft that the worker would not bottom out if he/she fell?

Some flotation device straps inflate when striking water. Some harnesses have such straps. If the natural conditions are reasonable - won't break neck in landing due to negligible fall?, no sharks, no fast current, no ice, no drowning possibility, the boat will rescue adequately etc., then it is possible to include water unless a hazard can be asserted.

OSHA Interpretations always are specific like court decisions. If you can demonstrate infeasibility of fall protection in a case history, let's hear it! Otherwise use both flotation and FP and watch the distances, mobility and retrieval under foreseeable work conditions.

OSHA 2 9 04 interpretation FP on docks and bridges Fall Protection under Part 1926 Subpart L "The structures that you refer to as work docks or work bridges fall within the scope of Part 1926 Subpart L (Scaffolds). This classification is significant in that it establishes the threshold height for requiring fall protection.

Section 1926.450(b) defines a "scaffold" as: Any temporary elevated platform (supported or suspended) and its supporting structure (including points of anchorage), used for supporting employees or materials or both.

"Platform" is defined as: *a work surface elevated above lower levels. Platforms can be constructed using individual wood planks, fabricated planks, fabricated decks, and fabricated platforms.

"Lower levels" mean: areas below the level where the employer is located and to which an employee can fall. Such areas include, but are not limited to, ground levels, floors, roofs, ramps, runways, excavations, pits, tanks, materials, water, and equipment.

Here, the structures fall within the definition of a scaffold as set forth in Subpart L. As described, the work docks or work bridges are supported platforms that provide a temporary elevated work surface over water to support employees and construction materials during the course of constructing bridges. They are temporary because they will be removed from the site at the job's completion.

Note that in the preamble to the scaffold standard (volume 61 of the Federal Register at page 46065), the significance of whether the structure is temporary is discussed:

OSHA has carefully analyzed all of the comments and data available in the record and determined that it is appropriate to maintain the 10-foot fall protection in the final scaffold standard, as proposed. * * * This level differs from the 6-foot threshold for fall protection in subpart M (Fall Protection) for other walking/working surfaces in construction because scaffolds, unlike these other surfaces, are temporary structures erected to provide a work platform for employees who are constructing or demolishing other structures. The same features that make scaffolds appropriate for short-term use in construction * * * make them less amendable to the use of fall protection at the time the first level is being erected.

Note also that the Agency stated in this section of the preamble that scaffolds are used to provide a work surface for workers who are "constructing...other structures." In the instant case, the work docks and work bridges only provide a temporary surface from which workers can work on other structures.

The threshold height at which fall protection is required is set by ﾧ1926.451(g)(1), which states: Each employee on a scaffold more than 10 feet (3.1m) above a lower level shall be protected from falling to that lower level...

The particular type of fall protection required depends on whether the scaffold is one of the specific types described in ﾧ1926.451(g)(1)(i) through (g)(1)(vi). If the work docks and work bridges fall within one of those categories, you must provide the fall protection described in the applicable section.

For all scaffolds not otherwise specified in paragraphs (g)(1)(i) through (g)(1)(vi) of this section, each employee shall be protected by the use of personal fall arrest systems or guardrail systems meeting the requirements of paragraph (g)(4) of this section.

Additional requirements under ﾧ1926.106 .

Note that, when working over water, ﾧ1926.106 requires an employer to provide Coast Guard-approved life jackets or buoyant vests, ring buoys with at least 90 feet of line, which are readily available for emergency rescue. Also, a life saving skiff must be immediately available. These requirements are in addition to the fall protection requirements of scaffolds and walking/working surfaces.

I know in general how NIOSH and ACGIH generates their standards. However, I recently had a question asked of me for more detail. Is there any place that I can go to get the general synopsis?

The answer is a whole world of contribution to voluntary standards development: ANSI, ASTM, SAE, UL, ASME, AISC, ASCE, ISEA etc. - you can only belong physically to so many committees - so you must choose.

Your point of view is always unique and so consensus is reached through discussion. Behind all safety committees within their scopes are the specific engineering issues and human factors that trap workers often one at a time who have limited education or awareness, and circumstances that foreseeably lead to harm if not addressed. OSHA's 5(a)(1) and 5(a)(2) present the duty to each employer. OSHA's regulations often play catch up with published voluntary standards if they are clear in their direction.

We suggest you read through the Accident Prevention Manual published by the National Safety Council and updated every 4 years to get a feel for the hundreds of voluntary standards which all need new blood on their committees.

If I am the GC on a project what is my liability with regard to the safety practices of my subcontractors? Many times I only have a superintendent onsite so I rely on them heavily.

There is OSHA to consider and third party liability to consider in the state where an incident may occur. Since the Summit Construction case, OSHA has restricted the application of its multi-employer policy to GC's that have onsite inspection and active types of control in evidence. This is hard with residential construction because there is often no subcontractor supervision. However larger projects have several GC representatives and often control the rough carpentry and guardrails instalation and repair.

With regard to liability from an injured party that brings a lawsuit against the GC, state law is over-riding any OSHA issue such as 1926.16. The key issue is that several states have determined that the WC of the sub is a shield for the GC who pays the sub for that WC premium and the GC is therefore immune from lawsuits eg Florida. However most states have negligence with control. Therefore across the United States the general rule is to follow the contract which gives the GC total control (responsibility) for safety onsite including all subcontractors and invitees. The five western states required a written plan of hazard recognition by each contractor and solutions for those hazards in advance of the work and to be handed to the next higher level of subcontractor. The general rule is that the GC must hire subcontractors responsibly and monitor safety not just accept their safety plan.

Where can I find information on subsystems for horizontal lifelines (Z359). I'm looking for information on shock absorbers. Are they required on horizontal lifelines?

We are not aware of a code requirement for in-line shock absorbers. You must understand that there are pros and cons to having an in-line shock absorber.

First, they reduce the horizontal end forces being applied to the supporting structure.

Second, they generally will significantly add to the deflection of the lifeline - thereby requiring a greater vertical clearance envelope.

Third, they generally add to the cost of the lifelines, but may reduce the cost of the supports.

Whether they are needed or not should be determined by the Qualified Person (engineer) involved in designing the system. If they come as part of an off-the-shelf temporary lifeline product, then they absolutely must be used with the components of that system.

I believe that the Z359 reference you are looking for is Z359.17 - which hasn't been released yet, but even when it is, I doubt that it will REQUIRE in-line shock absorption.

I know that all components of a fall arrest system must be compatible, but am not familiar with all the various types of equipment on the market.

The challenge is an employee who must have a higher weight capacity lanyard. I can find self-retracting lanyards that can be fitted with a shock absorbing pack to increase their capacity, but can not find a 'regular' lanyard that can be fitted with such a device. Not being very knowledgeable about this equipment, I'm guessing that adding a shock absorbing pack to a straight lanyard would make it longer than the 6 ft. max. Is the self-retracting lanyard w/shock absorber the way to go, the only way to go, or is there some other equipment that would be safer?

1. Many manufacturers have two product lines currently for fall protection, one that meets OSHA and A10.32 and another which is listed as Best Practice, the Z359-2007 Fall Protection Code. The latter is overwhelmingly critically important. For example - the gate strength of snaphooks. OSHA is 220 lbs/350 lbs (nose/lateral); Z359-2007 is 3,600 lbs all directions. That is a huge difference. Do not be complacent with Fed OSHA Subpart M which is from 1994 and is out of date. Gate distortions, especially large snaps can be lethal.

2. Sharp edges are a known hazard to the slender 3/16" dia. SRL cables perhaps in most impromptu applications. The use of Leading Edge SRL's (S/A at the snaphook end) is taking center stage due to increasing cable failures when ironworkers attach at or below foor level to open steel joists with beamers which is illegal 1926.757(a)(9) and subject to twisting loose without any engineering input. Also the cable WILL cut over laid deck panels if a fall over the edge occurs. Need that extra shock absorber!

Two catastrophes you do not need! Check out the educational site www.FallSafety.com archives and FAQ for more field situations that distributors of fall proptection will not know about to advise and which few manufacturers will know about at the field level.

Add to this, the weights in the 400 lbs area, you should be aware that the new test weight (torso) in Z359-2008 onwards is approx 282 lbs(310/1.1)not 220 lbs. There is a section in my Introduction to Fall Protection 3rd ed. which follows OSHA Sub M App C and explains your proportional calcs for you. Manufacturers have got up to 400 lbs and a little beyond for lanyard systems and one or two for SRL's too. Need to call directly. Suspension tolerance gets dicey with heavier weights.

Lanyards can be any length, just a max. 6 ft free fall unless there are clearance restrictions.

For compatibility of parts you need an independent mechanical engineer knowledgable in fall protection to run the calcs on the topology of snaphook/D-ring field contortions based on your applications.

Components from the same manufacturer are best but is you have a policy of "let the worker choose the most comfortable harness) then you are back to compatibility - never assume that parts are compatible from manufacturer to manufacturer. Tie all this together with a Program Administrator, see Z359.2.

ANZI 359.13-2009 indicates that the user must weigh within the range of 130 lbs to 310 lbs. One of my clients has several large distribution centers across the country and their order pickers are required to use fall protection when operating the lifts. My contact indicated that somewhere throughout their organization it is likely some of these employees may exceed the 310 pound limitation or not meet the 130 pound limitation.

Are there any exceptions to this standard? Are there lanyards available for people over the 310 lbs limitation that still would meet the standard? If not, then the only alternative would be to restrict these employees from jobs requiring fall protection.

Any thoughts on American Disability Act (ADA)? I am not an ADA expert or employment law expert, but I would think that if the standard limits the weight then the company would be on safe ground to write the limitations into the essential job description.

OSHA App. C of Subpart M addresses outside of the weight range, Z359 does not. Introduction to Fall Protection 3rd edition has a page addressing outside range (higher). Concern with higher weights is the suspension tolerance using present straps on arteries and veins especailly in the thigh area when the research has not been done. Shifting weight instruction from leg to leg is the present way of handling this.

A number of manufacturers address harness and device limits to 400 lbs. Limited range of equipment should include SRL's increasingly. You will have to ask about the 130 lbs but I think that higher g-force is outcome with present limit. Reducing that produces more distance for arrest but a different mechanism breakaway is needed. 10g was limit in early standards drafts but dropped due to difficulty addressing outside present range.

I am currently researching parapet height rules ﾖ mainly for construction clients and trades other than roofer who may be on a roof, near parapets without standard guardrails. I found several places in the Dr. Ellis "Introduction to Fall Protection, 3rd edition" that speak to optional "parapet minimum 30 inches + 12 or 10 inchesﾔ guidelines. I recognize this as an old OSHA interpretation (I used to be an OSHA officer) but I cannot find current supporting documents from OSHA. I think the sum of height and width must be 48" with minimum height 30" - I call it a flopguard. I would like to see guardrails at 45" minimum generally.

My questions:

1.What are the references for this guideline?

2.Does EFSS still use this guideline?

Answer to 1. OSHA Proposed General Industry Standard 4 10 90 so therefor de minimis. Maybe one day we will see it in final print. Answer to 2. Very much so, it is applicable in many areas.