Final answer:
The exact percentage of fatalities among would-be rescuers in confined space incidents is not specified, but historical examples like the Triangle Shirtwaist Factory fire underscore the high risk they face.
Step-by-step explanation:
The question deals with the hazards associated with working in confined spaces and the risks to would-be rescuers in such environments. Though the exact statistic is not provided within the information, we can deduce from historical events like the Triangle Shirtwaist Factory fire that fatalities in workplace disasters can be significantly high, and in many cases, those attempting rescue are also at great risk. In the Triangle Shirtwaist Factory incident, firefighters were unable to rescue the workers leading to a high number of fatalities.
The dangers of confined spaces include poor ventilation, which may result in insufficient oxygen or the presence of toxic gases, increasing the risk of injury or death. Moreover, limited access and egress can hinder rescue operations, putting both the initial victims and potential rescuers in jeopardy. Therefore, safety measures including proper training, equipment, and emergency procedures are critical to prevent such tragedies and protect those who would attempt rescue.