However, there was nitrogen inside the pipe as it had been formerly connected to the oxygen feed mixer. As there was no warning sign indicating it as a confined space or to indicate that the pipe contained nitrogen, the workers had no way to identify its presence. Worsening the situation, nitrogen cannot be detected using human senses as it is both odorless and tasteless. Admittedly, nitrogen is potentially dangerous at high concentrations as it causes asphyxiation.
As the workers entered the pipe and as they covered the mouth of the pipe with plastic sheet, they were overcome by nitrogen. When one of their coworkers looked into the pipe through an opening in the plastic sheet, he found both of them lying unconscious. Immediately, the plant emergency response team was informed. They arrived and took both of the workers out of the pipe. They were given cardiopulmonary resuscitation. Thereafter, they were transferred to hospital by ambulance. Both of them were in critical condition and were given oxygen therapy for about a week. Thereafter, he was released and took a week’s rest at home. In total, the person lost about two week’s work.
Soon, there was an OSHA visit and the company was fined for the accident. In addition, the company was made to improve its safety standards immediately.