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Document ID (ISN)53067
CIS number 90-242
ISSN - Serial title 0172-8334 - Humane Produktion - Humane Arbeitsplätze
Year 1988
Convention or series no.
Author(s) Schmider F.
Title Descent into manholes - The air in manholes may be deadly
Original title Einsteigen in Schächte - Die Luft im Schacht kann tödlich sein [in German]
Bibliographic information 1988, Vol.10, No.8, p.6-9.
Abstract Carbon dioxide, methane and hydrogen sulfide are the most hazardous gases that may occur in manholes. Two examples are used to illustrate that natural ventilation may not suffice to remove all toxic concentrations. Manholes must be supplied with fresh air forced all the way to the bottom. In addition, measurements of the CO2, CH4 and O2 concentrations are necessary prior to entry.
Descriptors (primary) carbon dioxide; hydrogen sulfide; monitoring for air contamination; manholes; mechanical ventilation; methane
Descriptors (secondary) occupational safety; workplace monitoring; acute poisoning; work in sewers; underground work; ventilation; toxic substances
Document type D - Periodical articles
Subject(s) Commerce, services, offices
Broad subject area(s) Chemical safety
Browse category(ies) Ventilation
Confined spaces
Carbon dioxide
Aliphatic and alicyclic hydrocarbons
Inorganic sulfur compounds
Inorganic substances