Case Study 4: Workers Overcome by Toxic Gas During Reactor Washing

Summary

In April 2001, a tragic incident occurred at a food flavor manufacturing facility when a plant worker died and others were injured during a reactor cleaning operation. Key failures included the failure to recognize the reactor as a confined space, lack of a confined space entry permit system, inadequate detection of toxic gases, and insufficient training and safety equipment for workers. The accident emphasized the need for comprehensive risk assessments, proper identification of confined spaces, and the implementation of safety procedures, training, and suitable protective gear to prevent similar incidents in the future.

Takeaways

• 😀 Failure to recognize the reactor as a confined space contributed to the incident. Confined spaces should be identified and managed properly.
• 😀 🚷 No confined space entry procedures or permit-to-work systems were in place, putting workers at risk during the cleaning operation.
• 😀 💨 Toxic gases, such as hydrogen sulfide, were undetected, causing hazardous conditions inside the reactor.
• 😀 😷 Inadequate personal protective equipment (PPE), like paper masks instead of air-purifying respirators, exposed workers to harmful gases.
• 😀 🧑‍🏫 Workers were not adequately trained in confined space entry or emergency procedures, leading to confusion and unsafe actions during the incident.
• 😀 🔄 The process of reactor inspection and cleaning, including multiple discharges and inspections, involved unnecessary risks due to a lack of safety protocols.
• 😀 🆘 No confined space attendant was assigned to monitor safety during the cleaning operation, leading to delayed response times and further injuries.
• 😀 ⚠️ A proper risk assessment, including identifying and mitigating potential hazards like toxic gas exposure, was not conducted prior to the cleaning task.
• 😀 🌬️ The absence of mechanical ventilation or regular air testing allowed the toxic atmosphere inside the reactor to go undetected until it was too late.
• 😀 🔧 Safe work procedures for non-routine tasks like reactor cleaning were not in place, leading to confusion about proper safety measures.
• 😀 🏫 The incident highlights the need for ongoing safety training, including confined space entry procedures and the use of appropriate PPE for workers.

Q & A

What was the initial issue that led to the accident in the thermal processing room?

The initial issue was the discovery of leftover salt residue in the reactor after discharging the product to the fermenter, leading to multiple unsuccessful attempts to clean it out.

Why did the plant washer experience difficulty while cleaning the reactor?

The plant washer experienced difficulty due to the strong smell inside the reactor, which likely resulted from the presence of toxic gases, such as hydrogen sulfide, which were not detected.

What safety precautions were overlooked during the reactor cleaning process?

Key safety precautions, including confined space entry procedures, gas testing for toxic gases, proper personal protective equipment (PPE), and a formal permit-to-work system, were overlooked.

What was the cause of the workers' exposure to toxic gases?

The workers were exposed to toxic gases like hydrogen sulfide because the presence of these gases was not identified beforehand, and proper ventilation or gas monitoring was not implemented during the cleaning process.

How did the supervisor attempt to rescue the unconscious plant washer?

The supervisor attempted to revive the unconscious plant washer by slapping him, but when he also became unconscious due to toxic gas exposure, colleagues had to pull him out, unaware that the plant washer was still inside the reactor.

What were the main flaws in the confined space entry procedures?

The reactor was not identified as a confined space, and there were no established procedures for safe entry. The workers were not properly trained for confined space work, and no confined space attendant was present to monitor safety.

What equipment was used by the workers, and why was it insufficient?

The workers wore a basic paper mask, which was insufficient to protect against the toxic gases. They should have used air-purifying respirators instead, especially given the hazardous environment inside the reactor.

What key lesson does the incident teach regarding confined space work?

The incident underscores the importance of identifying confined spaces, implementing a formal permit-to-work system, and ensuring that workers are trained and equipped with proper safety gear before entering these spaces.

What safety protocols should have been in place for this type of non-routine cleaning operation?

For non-routine operations like this cleaning task, there should have been specific safe work procedures, a confined space entry permit, adequate ventilation, and regular gas monitoring to ensure the safety of the workers.

What is the significance of risk assessments in confined space work?

Risk assessments are crucial to identify potential hazards, such as toxic gases or poor ventilation, before workers enter a confined space. They help in determining the necessary safety measures, equipment, and procedures to mitigate those risks.