Breast_derrick.gif
Summary
Description Breast derrick.gif |
English:
"Breast derrick" means a derrick without boom. The mast consists of two side members spread farther apart at the base than at the top and tied together at top and bottom by rigid members. The mast is prevented from tipping forward by guys connected to its top. The load is raised and lowered by ropes through a sheave or block secured to the top crosspiece.
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Date |
Unknown date
Unknown date
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Source | https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=9832&p_table=STANDARDS |
Author | Occupational Safety & Health Administration, U.S. Department of Labor |
Licensing
Public domain Public domain false false |
This work is in the
public domain
in the United States because it is a
work prepared by an officer or employee of the United States Government as part of that person’s official duties
under the terms of
Title 17, Chapter 1, Section 105
of the
US Code
.
Note
: This only applies to original works of the Federal Government and not to the work of any individual
U.S. state
,
territory
, commonwealth, county, municipality, or any other subdivision. This template also does not apply to postage stamp designs published by the
United States Postal Service
since 1978
. (See §
313.6(C)(1)
of Compendium of U.S. Copyright Office Practices). It also does not apply to certain US coins; see
The US Mint Terms of Use
.
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This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights. |
https://creativecommons.org/publicdomain/mark/1.0/ PDM Creative Commons Public Domain Mark 1.0 false false