LETTERS TO THE EDITOR
The benefit of multiple anchors depends on the angles of descent
I am writing in response to the article in the June 1986 issue of FIRE ENGINEERING entitled “Vertical Stokes Lower via a Roof System” by Kenneth J. Brennan.
In reference to a multiple anchor, Mr. Brennan states that, “… running a piece of rescue rope or webbing around two or more… objects… divides the full weight of the descending pull between or among the anchors.” He goes on to say, “… a 300-pound pull on a single substantial object might stress it enough to pull loose. However, if you run the rescue rope around, say, an air conditioning unit, a chimney, and heavy pipes, that 300-pound pull is now divided by the three objects, netting a 100-pound pull per object.”
What Mr. Brennan claims seems correct, but in reality and theory he is quite wrong. I understand that he is trying to convey information that should only be used in an emergency with minimum equipment and manpower; however, I believe that any firefighter (career or volunteer) who is capable of using the equipment and skills described by Mr. Brennan, should also possess knowledge of some of the rudiments of technical rescue. And this involves knowing better than to evacuate a litter, emergency or not, without making sure that the angles are as narrow as possible.
It is common practice, when using multiple anchors, to use them in an equalized fashion—without exception. However, equalized or not, when the angle formed by the anchor rope, from the attachment to the rope, equals 120°, the stress applied to each anchor equals the total stress applied by the load. That is, to use Mr. Brennan’s example, if a 300-pound load was applied to the rope going around two anchors and the angle formed was 120°, a 300-pound force would be applied to each of the anchor points. Simple physics proves my point.
With three anchors, the mathematics changes slightly, but it is important to realize that as the angle described becomes larger, the stress applied to each anchor point substantially increases. For example, for an angle of 160°, the stress applied to each anchor point is twice the primary load (600 pounds for our example).
It one is unable to equalize multiple anchors, it is probably just as safe, and possibly more Side, to go with the single best anchor available.
I teach technical rescue locally, at the University of Akron, and around the country; I am also a professional firefighter/paramedic. So, I am aware of the emergency situations that Mr. Brennan refers to and I feel obligated to set the record straight in hopes that mistakes as I described do not continue to endanger members of my profession unnecessarily.
Donald C. Cooper
Director of Education
National Rescue Consultants
Cuyahoga Falls, OH
FIRE ENGINEERING wants to know your thoughts on and reactions to not only articles that have appeared in our pages, but to any issues that concern and impact the fire service.
FIRE ENGINEERING’s Letters to the Editor column is set up to serve as an informational exchange among all facets of the fire service, suppression, prevention, protection, and investigation. Your ideas and input may prove beneficial to your own department, to the department in the next district, and maybe to the department on the other side of the Mississippi.
Your feedback also enables us to shape our editorial content to meet your department’s (and others’) particular needs. So, write to us. And, again, thanks for your help and support.
Tom Brennan Editor
Hazmat guide legalities?
I am quite concerned about the “build your own” hazardous materials reference series currently appearing in FIRE ENGINEERING.
Although the articles are interesting, informative, and a good refresher, I wonder about the legal implications. When I took the fire science program (too) many years ago, one instructor had us look up chemicals and fill out similar data sheets. When I asked what I should do with the notebook, he said, “Put it on the pumper.”
The company lawyer and several neighboring chiefs said, “Throw it away.” Their justification was that if I had misspelled a word or confused diethylwhoever with diethylwhomever, we could be in big trouble.
I feel the same is true for your recommendation to “… make the collection of this data into a parochial reference work for his response area.” As you state, “He would, in effect, make his own outline….” That won’t be worth a hill of beans in court. In this sue happy society, you’ve got to stick to the National Fire Protection Association and Department of Transportation manuals or the Manufacturers Safety Data Sheet.
Alan T. Price
Assistant Chief
Point Pleasant Fire Department
Rochester, NY
Liability suits can hamstring protection services
It was a pleasure reading your July 1986 editorial on “Who’s Really Liable?” We are a fire apparatus manufacturer concerned for the uncontrolled costs and misallocation of resources caused by the liability crisis.
When a manufacturer has to accept responsibility for individual careless or unsafe use of equipment, it will bring to a stop or slow the development of new technology in firefighting and lifesaving equipment. The fire protection and lifesaving services and professions, along with responsible manufacturers, must work together and respond to these ridiculously high liability awards which are creating high insurance costs.
As a manufacturer, we design, build, and assemble products with safety in mind. We can only put so many warning labels on the equipment. Then, we must rely on the respective departments to instruct, regulate, and enforce proper rules of operation. Only when the departments and their supporting taxpayers realize what liability suits are adding to the cost of equipment, will we receive the needed action for better tort laws.
You are right, the settlement in Massachusetts is a “no win” lesson for all of us except the law firms. Until the taxpayers, including lawyers and politicians, realize this, we will be unable to respond to the growing needs of the fire and life protecting services.
The American business system is based on competition and the free market. Now the legal system is threatening to destroy our economy and growth opportunities by attempting to create a failsafe society.
Douglas A. Ogilvie
Chairman and Chief Executive Officer
Pierce Manufacturing, Inc.
Appleton, WI
