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John has been assigned to make some minor repairs in an elevated work location. Because John’s employer is conscientious about safety, he has been equipped and trained to use a fall-arrest harness with a 6-foot shock-absorbing lanyard and has been told about self-rescue techniques. After fastening his lanyard to a secure anchorage, John begins his tasks. Suddenly, a pigeon, disturbed by John’s work activities, flies out of a small area and startles John. He steps back suddenly and falls from the platform where he was working. The shock absorber on his lanyard extends to reduce the impact forces on his body, although it is still a hard fall, and John is left dangling in an area where he can’t reach any of the structure to be able to perform self-rescue. All he can do is yell for help and wait while the harness binds painfully around his thighs. The industrial facility that employs John does not have a trained high angle or confined space rescue team. The management of the facility had previously decided that the cost of equipping, training and maintaining an in-house team was prohibitive and unnecessary since they had a good safety record in the workplace. The plant has a standing contract for a confined space rescue standby team during turnarounds but they are not available for response in the plant except during turnarounds. Other workers hear John’s cries for help and decide to call 911 for assistance from the local fire department. The fire department has a big, shiny rescue truck but they are only trained and equipped for vehicle crash extrication, not high angle or confined space rescue.. The fire department
responds and arrives at the site within 10-minutes of the call to 911.
They quickly establish verbal contact with John to assess his condition.
John tells the firefighters that he is not hurt but he can’t get
back to safety without help. The firefighters determine that John is beyond
the reach of the ladders they carry on their truck, he cannot be reached
by crane or manlift and that a rope rescue will be necessary. They call
for mutual aid from a nearby fire department with high angle rescue capabilities
but it will be a 25-minute response before they arrive. When the mutual aid rescue team arrives, they quickly set up a raising system to be able to release John’s lanyard from its anchor point and then lower him to the ground. John has no vital signs and CPR is started during the trip to the hospital. Unfortunately, the hospital personnel are unable to restore John’s heartbeat and he is pronounced dead. What Happened? 29 CFR 1910.66 Powered Platforms for Building Maintenance, Section (e)1, Care and Use says when vertical lifelines are used, each employee shall be provided with a separate lifeline and the employer shall provide for the prompt rescue of employees in the event of a fall or shall assure the self? rescue capability of employees. John’s employers had equipped John with a fall-arrest system and trained him in self-rescue as required by OSHA. He was uninjured by his fall but he died before he could be rescued. Motionless or unconscious suspension in strap harnesses for even a very short time, sets up a blood venous pooling effect which becomes dangerous if rescue methods do not address this effect. Oxygen flow into the respiratory tract plus slight elevation of the legs is vitally important for the rescue of fallen workers. Speedy rescue techniques are vital. Workers in pre-fall training should be told to keep body parts moving frequently in a post-fall wait for rescue; The term "Prompt rescue availability" means "immediate prompt relief of suspension"; Rescuers need special training for understanding suspended worker physiology Harness Testing At the request of OSHA, the United States Air Force’s Aeronautical Equipment Laboratory and the Aeromedical Laboratory at Wright-Patterson Air Force Base conducted a research program aimed at demonstrating the relative effectiveness of various types of fall protection harnesses.2 The objectives of the test program were:
The test subject sample consisted of 13 volunteers who passed an extensive medical screening before the tests. The subjects were gently raised off the floor while wearing the test harness until their feet could not touch the floor for support. No corrective movements or strap adjustments were permitted once the subject was suspended. The subjects were suspended until their subjective tolerance was reached or until symptoms of hypotension (low blood pressure) or syncope (fainting) developed, which warranted a medical decision to terminate the test. The measurements
taken included an electrocardiogram, blood pressure, respiratory rate,
test duration and subjective comments. Each harness was fitted snugly
to the subject in accordance with the manufacturer’s instructions,
but not to the point where the range of extremity motion or torso movement
were restricted.
One case of syncope (loss of consciousness) occurred in a subject suspended in a full-body harness. The syncope occurred while the subject was being lowered from the suspension. The subject had requested termination of the suspension because of symptoms of feeling flushed. The subject was unconscious for approximately 30 seconds, and recovered quickly without any medically adverse effects when placed in the supine position. The electrocardiogram revealed a significant bradycardia in which the heart rate decreased to approximately 30 beats per minute. The bradycardia persisted for approximately 20 seconds before returning to a normal sinus rhythm and rate. In almost all instances the heart rate and respiratory rate increased while the subject was suspended in a harness. The magnitude of the increase in heart rate and respiratory rate was variable among subjects and harness types. Cardiac dysrhythmias that were observed included tachycardia and premature ventricular contractions as well as bradycardia. WARNING! A worker who has suffered a fall and is suspended in his harness is a true medical emergency. Just because they are hanging in a harness doesn’t mean you “have all day” to perform the rescue. Rescue has to be planned, practiced, and performed quickly and effectively or the victim may very well die before the “rescue” finally occurs. 1 U.S. Department of Labor, Occupational Safety and Health Administration (US DOL/OSHA) 200 Constitution Avenue NW. Washington, DC 20210. 2 Fall Arrest and Post? Fall Suspension, (AFAMRL?TR?84?021), Air Force Aerospace Medical Research Laboratory, Wright? Patterson AFB, Dayton, Ohio: 1984 This article was
published in the April 2000 edition of BIC Magazine and is posted here
by permission of the author. This paper appears in the eLCOSH website with the permission of the author and/or copyright holder and may not be reproduced without their consent. eLCOSH is an information clearinghouse. eLCOSH and its sponsors are not responsible for the accuracy of information provided on this web site, nor for its use or misuse. |
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