- Publication Date:
- Publication Type:Notice
- Fed Register #:41:15483-15484
- Standard Number:
- Title:Variance
- Abstract:
Variance granted to T. A. Loving Company from the standards originally prescribed in 29 CFR 1918.74(a)(9)(i), concerning load indicating devices required by 1918.74(a)(9) on cranes. Effective April 13, 1976, and it shall remain in effect until modified or revoked. [1918.74 has been reserved, and present provision governing variance is 1918.66, specifically 1918.66(f)(1)(i)].
DEPARTMENT OF LABOR
Occupational Safety and Health Administration
[V-74-43]
T. A. LOVING CO.
Grant of Variance
I. Background. T. A. Loving Company, P.O. Drawer 919, Goldsboro, North Carolina 27530 made application pursuant to section 6(d) of the Williams-Steiger Occupational Safety and Health Act of 1970 (84 Stat. 1596; 29 U.S.C. 655) and 29 CFR 1905.11 for a variance from the safety standards prescribed in 29 CFR 1918.74(a) (9) (i). The standard requires that the load indicating devices required by § 1918.74(a) (9) on cranes used to load or discharge cargo into or out of a vessel meet certain specified criteria, except that a dynamometer or simple scale alone will not meet this requirement. The facilities affected by this application are all of the applicant's private and contract worksites requiring the use of marine equipment.
Notice of the application was published in the FEDERAL REGISTER on August 23, 1974 (39 FR 30560). The notice invited interested persons, including affected employers and employees, to submit written data, views, and arguments regarding the grant or denial of the variance requested. In addition, affected employers and employees were notified of their right to request a hearing on the application for a variance. No written comments or requests for a hearing have been received.
II. Facts. Section 1918,74(a) (9) (i) requires that every crane used to load or discharge cargo into or out of a vessel be fitted with a load indicating device meeting certain specifications, except that a dynamometer will not meet this requirement.
The applicant engages in the construction of bridges and docks over or near navigable waters. The construction projects usually last from six months to two years. When one project is completed the equipment is moved to the next work site. Some of the equipment is often left on the work barges for transportation to the next location. On arrival, cranes are used to remove materials and equipment from the barges. There are no below deck loading or storage areas, the load hook is always in plain view of the crane operator(s) performing the loading or unloading operations with the crane or derrick, with signals always given from the hook points of the load. The lifts are always of materials with known or calculable weights.
The applicant requests a variance to allow the use of dynamometer on its mobile cranes rather than load indicating devices as required by § 1918.74(a)(9) (i). Although the standard states that the dynamometers are not an acceptable weight indicating device, the applicant's work situation and the type of dynamometer used both differ from those considered when the standard was written. The work situation differs from that of marine shippers in the following ways: (a) the scale of the operation is much smaller, (b) the applicant's use of floating equipment is primarily for storage and for supply work platforms as a point of operations, (c) all items lifted are above deck with the hook visible to the crane operator, (d) the same equipment is utilized at each work site, and (e) the same personnel make up the crew at each site.
The dynamometer which the applicant proposes to use on all lifts which would be subject to the standard is the Model AN or ANC Dillon Dynamometer or the equivalent. These dynamometers would be of either 0-50,000 lbs. or 0-100,000 lbs. depending on the capacities. Overloads of up to 25 percent can be sustained with no injury to the calibration, and the safety factor is 3 times their rated capacity. The usual dynamometers are spring devices which are commonly inaccurate. The dynamometers which the applicant uses operate through deflections of a special alloy steel beam to give load weight to ±2 percent of actual load weight. The devices are individually calibrated with the load weight indicated in pounds on the dial face.
The dynamometer would be attached to the hook line either by means of a safety hook or adequately sized screw-pin shackle. The load rigging, and/or slings, would be attached to the opposite end at the device in the same manner. In most lifts the dial of the dynamometer would be visible to the crane operator allowing for self reading of the indicated load weight. At those times when the crane operator might not be able to adequately read the face of the dial indicator personally, due to the boom angle or the configuration of the load, the maximum lifting capacity of the crane in use would be computed in advance of making the actual lift by measurement of the intended actual radius at which the crane would be operating and consequently planning for a lift not in excess of the crane's rated capacity at such radius. Personnel stationed at the hook point would then determine by observation if such maximum loading would be reached prior to a cleared lift of the load to be handled. The dial of the dynamometer would be visible to this person. If the load weight reached or exceeded the rated capacity, the lift would be stopped by signal. Arrangements could then be made to reduce the operating radius or diminish the load weight to be lifted in order to assure a safe lift.
III. Decision. 29 CFR 1918.74(a) (9) (i) states that the type of load indicating device used on cranes shall be of a type which provides: (a) a direct indication in the cab of actual weight hoisted or a means of determining this by reference to crane ratings posted and visible to the operator; or (b) an automatic weight-moment device or computer providing indications in the cab according to radius and load at the moment; or (c) a device which shall prevent an overloaded condition. The standard also states that the use of a dynamometer or simple scale alone will not meet the requirements of (a).
A dynamometer differs from a load indicating device in two ways. First, a load indicating device is a permanent part of the crane structure while a dynamometer is portable and can be attached to the crane in use. Second, most dynamometers are spring devices, while load indicating devices measure the deflection of a piece of metal.
The purpose of not permitting the use of dynamometers is the unreliability and inaccuracy of the commonly used spring operated dynamometers. This is particularly important in situations where the load is not familiar or is not visible to the operator.
In the applicant's situation the cranes are used only to lift known items of construction materials or equipment. There are no below decks loading or storage areas, and the items lifted are all of known or calculable weights. The personnel involved in making the lifts at all locations are members of a permanent work crew and are familiar with the cranes and dynamometers as well as with the materials and equipment being lifted. Supervisory personnel direct all lifts. This differs from the usual marine operation in which the personnel make lifts of unfamiliar cargo using the gear of various vessels.
The devices which the applicant proposes to use to measure the load are dynamometers in that they are portable and can be attached to whatever cranes are in use. However, they differ from the usual dynamometers in that they are not spring devices but operate through deflections of special alloy steel beams which require only .040" movement to indicate a full scale reading. These are extremely accurate and well-built dynamometers which are individually calibrated and give readings on the dial in pounds of ±2 percent of the actual load weight, and have a safety factor of 3.
For these reasons, it has been determined that by use of the AN or ANC Dillion Dynamometers the applicant is providing a place of employment as safe as that which would be obtained by complying with §1918.74(a) (9) (i) (a).
IV. Order. Pursuant to authority in section 6(d) of the Williams-Steiger Occupational Safety and Health Act of 1970, and in Secretary of Labor's Order No. 12-71 (36 FR 8754), it is ordered that T. A. Loving Company be, and it is hereby, authorized to use dynamometers on its cranes as load indicating devices in lieu of complying with the requirements of 29 CFR 1918.74(a) (9) (i), provided that the following conditions are met: (1) the affected cranes are used directly in connection with construction operations at the construction site; (2) the affected cranes are certified by an accredited agency; (3) the affected cranes shall not be used to lift cargo destined for shipment unless fitted with a load indicating device in compliance with § 1918.74(a) (9) (i); (4) all materials and equipment hoisted shall be marked with gross weights; (5) the dynamometers shall be used in conjunction with a boom radius and/or angle indicator; (6) the dynamometers used shall be AN or ANC Dillion Dynamometers or the equivalent. They shall not be spring devices, but shall be operated through reflections of a special alloy steel beam; shall be individually calibrated; shall give readings on the dial in pounds to ±2 percent of the actual weight (accuracies shall be known at all times and the errors applied to the reading), and shall have a safety factor of 3; (7) whenever possible the dial of the dynamometer shall be visible to the crane operator to allow self reading of the load weight; whenever the boom angle or load configuration prevents the operator from being able to see the dial, personnel shall be stationed in such a manner as to observe the load and the reading on the dial and signal the crane operator to stop the lift in the event of an overload; (8) the personnel involved in the lifts shall be members of a permanent work crew and trained for the job. Only supervisory personnel shall direct the lift.
As soon as possible T. A. Loving Company shall give notice to affected employees of the terms of this order by the same means required to be used to inform them of the application for variance.
Effective date. This order shall become effective on April 13, 1976, and shall remain in effect until modified or revoked in accordance with section 6(d) of the Williams-Steiger Occupational Safety and Health Act of 1970.
Signed at Washington, D.C. this 6th day of April, 1976.
MORTON CORN,
Assistant Secretary of Labor.
[FR Doc. 76-10647 Filed 4-12-76; 8:45 am]