If you're an industrial worker who has been exposed to small and confined spaces, you know how important it is to know the oxygen levels as well as how much carbon dioxide is present. If there is too much CO2, you could suffocate, which could result in brain damage or death. If you're working with your attorney to make a claim for a pit hazard in the workplace, it's important to know that the Occupational Safety and Health Administration does recognize the dangers of these areas.
In fact, one of the areas you may need to look out for is the space below a waterfall or water fountain in a shopping mall. It's not a common place to think of having pits, but with the required underground plumbing, it's possible that workers will need to go underground.
Normally, dangerous or hazardous pits require a permit to enter. Then, only those licensed or trained to enter can go inside with the assistance of other workers. These spaces in shopping malls may not require a permit, but they are still as hazardous as other kinds of pits.
In one referenced event, an employee entered a shopping mall pit, a small 3 by 3 opening, and quickly passed out. It turned out that the oxygen level wasn't taken at the site, but in one only 60 feet away, the oxygen level was only 13 percent. That same area was identified as having 11,500 ppm of carbon dioxide, which is enough to kill someone exposed over a long enough time period. These pits may have needed time to "air out," and absorb oxygen before anyone entered.
Source: United States Department of Labor, "OSHA Hazard Information Bulletins Asphyxiation Hazard in Pits: Potential Confined Space Problem," accessed Oct. 08, 2015