File:Bell telephone magazine (1922) (14754359304).jpg

Identifier: belltelephonemag19amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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Text Appearing Before Image:
finitions of heavy and mediumstorm loading which were subse-quently adopted in the National Elec-trical Safety Code, as discussed laterin this article. Areas on the map (Figure 5) inwhich heavy ice storms were re-corded are marked with pins withheads having a black background.The pin head code for showing thefrequency of occurrence of suchheavy storms is indicated at the bot-tom of this page. Areas in which me-dium ice storms only were experiencedare designated by pins having a whitebackground with black markings, thesame general type of code as in thecase of heavy storms being employedbut using black instead of white lines,crosses and dots to indicate frequencyof occurrence. PIN Head Code for Heavy Storms See map on opposite page Average Occurrence of Heavy Storms Coded At least once in 3 years Solid black Once in every 3-6 years Black with white stripe Less than once in 6 years Black with white cross Only one heavy ice storm Black with white spot 236 Bell Telephone Quarterly OCTOBER
Text Appearing After Image:
Fig. 6. N.E.S.G. STORM LOADING MAPSince 1926 this has served as a guide to the wire-using companies Again, to keep clear the distinctionbetween storm loading and stormdamage, this map indicates only theintensity and frequency of occurrenceof storm loads. As indicated later,in the design and maintenance of thetelephone plant the strength of con-struction and use of the more stormproof types of plant are varied tomeet the storm loads which experienceshows may be imposed. A map suchas that shown in Figure 5 serves itsmain purpose when it shows whichareas should be fortified against dam-age and service disruption. In those areas where heavy stormspredominated, the occurrence of me-dium storms has not been indicated.However, in sections where moststorms were medium, but in whichsome heavy storms occurred, pins with black background and pins with whitebackground are to be seen inter-mingled. The method adopted in posting themap results in a closer spacing of thepins in those areas in which

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