Edel-Kindwall Caisson Tables for Preventing Decompression Illness in Construction Workers
April 2013
NIOSH Docket Number 254, CDC-2012-0007
High pressure tunneling operations are used for some underground infrastructure projects. Compressed air is used to prevent seepage of water or to stabilize unstable soil conditions. Caisson work (a water-tight structure that allows underwater construction to be performed) can also involve elevated pressure worksites. This hyperbaric environment (ambient pressure and compressed air effects) exposes caisson and tunnel workers to the risks of decompression sickness (DCS) also called the “bends”. DCS is related to intravascular or extravascular bubbles formed during reduction of environmental pressure (decompression). The release of nitrogen bubbles into blood or tissues can result in obstruction of blood flow or pressure effects. Clinical manifestations of DCS include (but are not limited to) joint pain (“bends”), lytic lesions of bones (dysbaric osteonecrosis), cutaneous disorders (cutis marmorata), spinal cord and brain disorders (stroke, paralysis, paresthesias, bladder dysfunction, etc.), and cardiopulmonary disorders (shortness of breath [“chokes”]), arterial gas embolism).
More information can be found on the Decompression Sickness and Tunnel Workers page.
To view the notice and related material visit http://www.regulations.gov/, enter CDC-2013-0007 in the search field, then click “Search”.
Material Under Consideration
Federal Register Notice [PDF – 2,839 KB]
Criteria for interim decompression tables for caisson and tunnel workers [PDF – 17,353 KB]
G3A Air Interim Decompression Tables – Utilized for pressures in the range from 14 psi to 50 psi to be used at altitudes no greater than 800 – 1000 feet. [PDF – 17,353 KB]
G3A1 Air Interim Decompression back-up Tables for G-3A – Serves as a backup for Table G3A where environmental or individual conditions warrant, based on the most severe conditions which might be anticipated and under which such conditions should produce a decompression sickness incidence that is significantly improved over current practice. [PDF – 17,353 KB]
G3B1 Oxygen Interim Decompression Tables – Note that these should not be used unless the contractor is willing to obtain special training for the personnel involved and properly maintain the required oxygen equipment. [PDF – 17,353 KB]
G3C Air Saturation Interim Decompression Table – These should be used when operational needs or emergencies required workers to remain under hyperbaric conditions for more than 8 hours. [PDF – 17,353 KB]
French Tables [PDF – 246 KB]
A guide to the work in compressed air regulations 1996 [PDF – 943 KB]