Fall Protection for Iron Workers
It is imperative that you select only equipment that has been tested and approved to tie off at foot level or below.
- By Marty Sharp
- Jul 01, 2015
As most of us view life, iron workers live dangerously. We use all of the clichés over and over again. "Their lives are hanging by a thread." "They're at the top of the world." "Their life is on the line." Let's do our part to keep them hanging.
It can be discouraging. Year after year, we read the same statistics. Falls are among the top sources of injuries and fatalities on the construction site. At the same time, fall protection violations lead the list of OSHA citations annually.
We'll take a look at OSHA's fall protection standard. It's broad in scope, covering new construction, alterations, or repair of "structures" when the erection of steel takes place. Cranes, bins, hoppers, ovens, furnaces, amusement park rides, stadiums, bridges, trestles, overpasses, billboards, and light towers are among examples of types of structures covered, in addition to buildings. Some structures are specifically excluded from coverage. These include tanks, electrical transmission towers, and communication or broadcast towers.
The OSHA standard is a key. You must know and understand its requirements. However, it is only one part of what we look at as a five-piece puzzle.
Probably number one for you is "recognizing a fall hazard" when you see it. Obviously, you cannot deal with a problem if you are not aware of it. The eye test will often tell you when something is unsafe. Then, dig deeper! How can you mitigate the situation? Can the task be completed in another way? Many times, the answer is "no." What then can be done to protect the worker? It is your responsibility to deal with the hazard. Failure to do so may result in prosecution for willful intent or manslaughter if a death occurs. We read recently of a superintendent who was sentenced to jail for failure to provide fall protection.
You need a plan. We recommend a five-part program of understanding. Remember our five-part puzzle. These points are critical, not simply important, especially in the event of an accident.
1. Recognize the hazard
2. Understand the manufacturer’s instructions
3. Develop and record your company policy
4. OSHA regulations
5. ANSI standards
Let's look at each of them individually.
These instructions may claim to meet ANSI, in which case the actual use of the product must also comply. The manufacturer may put limits on the use of a product and, as a user, you must pay attention. For example, an eyewear manufacturer may claim compliance with Z87 but limit the use by including the statement, "beware of grinders."
Remember, as a minimum your internal regulations must meet OSHA requirements. They may be written around ANSI standards, even if not adopted by OSHA, or be of your own creation. However, once adopted internally, you must comply. Failure to do so can result in an OSHA violation.
Any portion of an ANSI standard adopted by OSHA, by amendment, becomes a regulation and compliance is mandatory. A user found "not in compliance" is subject to a fine.
A committee of manufacturers establishes a set of "best practices." These are simply voluntary standards with which the user may or may not comply. OSHA may adopt these standards as a whole or in part by amendment. Once adopted by OSHA, they become mandatory.
OSHA 29 CFR, Subpart R 1926.760
Basically, every employee walking or working more than 15 feet above a lower level must be protected. Most GCs restrict this to 6 feet. Paragraph 1926.760(a) says the worker shall be protected from fall hazards by:
1. Guardrail systems
2. Safety net systems
3. Fall restraint systems
4. Positioning device systems
5. Personal fall arrest systems
Acceptable criteria for each of these systems are spelled out in Appendix G in the standard.
The focus of this article is the plan for fall arrest systems.
When personal fall arrest systems are employed, they must meet the following criteria:
1. The maximum arresting force on an employee must be limited to 900 pounds when using a body belt.
2. The maximum arresting force on an employee must be limited to 1,800 pounds when using a harness.
3. The employee cannot free fall more than 6 feet or contact any lower level.
4. The employee must be brought to a complete stop, and the deceleration distance of travel must not exceed 3.5 feet or what the system allows.
5. The system must be strong enough to withstand twice the potential impact energy of an employee free falling 6 feet or the free fall distance allowed by the system, whichever is less.
Look at criteria 3 and 5 above. Both reference a 6-foot drop. Compliance may not be possible. A general contractor sent this question to OSHA and received the accompanying interpretation.
Subject: §1926.502(d)(16) Personal fall arrest equipment
Question: The provision in §1926.502(d)(16) requires that free fall distance be limited to 6 feet. It is impossible to design an attachment point that will allow me to limit the free fall to 6 feet. What are my obligations?
He received the following response:
Answer: §1926.502(d)(16) also requires that the maximum arresting force be limited to 900 pounds when the personal fall arrest system incorporates a body belt and 1,800 pounds when the system incorporates a body harness. If the employer has documentation to demonstrate that these maximum arresting forces are not exceeded and that the personal fall arrest system will operate properly, OSHA will not issue a citation for violation of the free fall distance.
Basis for Decision: U.S. manufacturers of fall protection equipment test their equipment in accordance with test procedures prescribed in ANSI standards (ANSI A10.14 and ANSI Z359), which call for equipment to be tested based on a 6-foot free fall distance. Unless the equipment has been tested for a free fall greater than 6 feet, the results are unknown. Therefore, if an employer must exceed the free fall distance, the employer must be able to document, based on test data, that the forces on the body will not exceed the limits established by the standard and that the personal fall arrest system will function properly.
How do we accomplish this? We must use tie-offs at foot level or below. All anchorage points must be rated for 5,000 lbs., or a safety factor of two, and remember, fixed systems or catenary line are like upside-down two-legged bridles.
Off-the-shelf systems to meet the need are available. However, all components of the system must meet the requirements of 1926.502. Connection shall be drop forged, pressed or formed steel, or made of equivalent materials. They shall have a corrosion-resistant finish, and all surfaces and edges shall be smooth to prevent damage to interfacing parts of the system.
D-rings and snaphooks shall have a minimum tensile strength of 5,000 pounds (22.2kN). They shall be proof-tested to a minimum tensile load of 3,600 pounds (15kN) without cracking, breaking, or taking permanent deformation. Snaphooks shall be sized to be compatible with the member to which they are connected to prevent unintentional disengagement of the snaphook by depression of the snaphook keeper by the connected member, or shall be a locking type snaphook designed and used to prevent disengagement of the snaphook by the contact of the snaphook keeper by the connected member.
Unless the snaphook is a locking type and designed for the following connections, snaphooks shall not be engaged directly to webbing, rope, wire rope, to each other, or to a D-ring to which another snaphook or other connector is attached.
Unless a locking type, the snaphook shall not be engaged to a horizontal lifeline, or to any object which is incompatibly shaped or dimensioned in relation to the snaphook such that unintentional disengagement could occur by the connected object being able to depress the snaphook keeper and release itself.
On suspended scaffolds or similar work platforms with horizontal lifelines which may become vertical lifelines, the devices used to connect to a horizontal lifeline shall be capable of locking in both directions on the lifeline.
Ropes and straps (webbing) used in lanyards, lifelines, and strength components of body belts and body harnesses shall be made from synthetic fibers.
Anchorages used for attachment of personal fall arrest equipment shall be independent of an anchorage being used to support or suspend platforms and capable of supporting at least 5,000 pounds or a safety factor of two (22.2 kN) per employee attached, or shall be designed, installed, and used as follows: As part of a complete personal fall arrest system that maintains a safety factor of at least two, and under the supervision of a qualified person.
Considerations and Questions Relating to This Off-the-Shelf Solution
1. Load: There are only a few retractables on the market designed for foot level drops and even fewer designed for below the feet drops. It is a good idea for the unit engineered into the system to have a mechanical shock absorber with a disk brake mechanism designed for free falls up to 78 inches when tied to a rigid tie-off point, keeping the impact to the body under 900 pounds, unlike some seatbelt-like mechanisms with a shock pack on the end. This type of unit would be in violation. Another benefit of the acceptable retractable is that the line is under tension during the drop. The web or wire coils back into the unit, and then the disk brake kicks in for a soft drop with less chance of lower-level contact. In addition, when dropping on a catenary line (not a rigid tie-off point), there is shock absorber capability in the line itself. It’s like jumping on a trampoline: On the way down, energy is absorbed. You just don’t bounce back up. This makes the impact to the line less, increasing the safety factor.
2. Q: Does where the drop occurs on the line affect the angle of deflection adding greater or less stress on either anchorage point?
A. Yes and no. Some engineers theorize that this would be a factor. Other engineers have theories that since the catenary line has sag and deflection, that the blow on the cable is a glancing hit and the hook slides a little bit, if that’s the same amount of energy over a longer period of time. The peak load is less. It’s very similar to when an employee falls head first. Many times, the shock pack will not deploy all the way because it takes time to bring the employee back into an upright position. In doing the physical test, the latter proves to be true. The middle of the span is worst-case scenario.
B. 3/8" galvanized cable has an M.B.L. (minimum break load) of approximately 14,000 pounds. So it's good for two people, right? Wrong!
Example: In the mid-1990s, my wire rope company sold a trailer manufacturer 100 feet of 3/8" cable with a large turnbuckle at one end. Unfortunately, my order desk didn't ask enough questions on what the application was. They strung it above the trailers and tightened it tight enough to play a song on it. They dropped a pulley on the cable and hooked a retractable to it; the employee could go along the top of the trailer stapling the roof on. When the supervisor, wasn’t looking one of the employees decided to use it as a zip line and run off the back of the trailer to see how far he could go down the line. The plan was for another employee to pick him up with a boom truck when he stopped. On the first attempt, the cable snapped. The employee was fortunate he just broke a few bones. If it was higher up, it could have been fatal. Obviously this was not an engineered system. Engineers use some of these factors when calculating deflection under load.
Choose Your Equipment Carefully
By nature, a skeletal structure is rising very slowly from the ground. Beams are narrow, providing a limited working surface. Work is constantly at the topmost point, meaning anchorages and tie-offs must be at a worker’s feet.
It is imperative that you select only equipment that has been tested and approved to tie off at foot level or below. Remember, "his life is on the line." I trust the above remarks have "gotten you thinking." Call me if I can be of help: 1-800-850-5914.
This article originally appeared in the July 2015 issue of Occupational Health & Safety.