The confined or enclosed spaces on barges may have an atmosphere that is unsafe, causing injury or death. The three main atmospheric hazards while working in a confined or enclosed barge space are:
These hazards might be found in any watertight compartment or other area on a barge with little or no ventilation.
The most hazardous confined or enclosed space conditions in barge operations occur while exposing workers to oxygen-deficient atmospheres and toxic atmospheres. Toxic vapors may be produced by the previous cargo or cleaning agents and could present significant health hazards. When encountered in confined or enclosed spaces, these agents produce vapors that are often heavier than air. This can cause displacement of air, reducing oxygen levels, which may be fatal. An oxygen-deficient atmosphere inside a tank can be caused by many factors such as:
An explosive or flammable atmosphere can develop from many sources. Some examples of these sources may include:
Before beginning work in, near or around a confined space or compartment, be sure to do the following:
Toxic atmospheres are generally the most difficult to identify and can only be determined through testing, which should only be conducted by a qualified person (i.e., marine chemist, competent person, etc.). The potential for a toxic atmosphere is always present and can come from several sources including:
Based on the hazards discussed above, entry into any confined/enclosed space or any space with limited ventilation space on a deck barge should be done with caution.
Two riggers were capping a sulfur well in a shallow bay, working from the deck of a barge equipped with a crane with a clamshell bucket. The employees dug around the well casing and then set a caisson around the wellhead. Standard procedures required them to cut off the casing and then weld a circular plate over the end. The first employee went into the caisson to wrap a sling around the pipe end, and was asphyxiated due to hydrogen sulfide gas. The second employee entered the caisson to rescue him, and was also overcome by the gas. Neither was wearing respiratory protection (i.e., airline or Self-Contained Breathing Apparatus). Both employees died.
OSHA Safety and Health Topics: Confined Spaces http://www.osha.gov/SLTC/confinedspaces
Shipyard Employment e-Tool: Ship Repair http://www.osha.gov/SLTC/etools/shipyard/shiprepair/sr_index.html
Take OSHAcademy Course 713, Confined Space Safety
Before beginning this quiz, we highly recommend you review the module material. This quiz is designed to allow you to self-check your comprehension of the module content, but only focuses on key concepts and ideas.
Read each question carefully. Select the best answer, even if more than one answer seems possible. When done, click on the "Get Quiz Answers" button. If you do not answer all the questions, you will receive an error message.