A federal investigation showed that failure to properly define the emergency response roles of employees during an isobutylene leak contributed to the severity of a 2019 chemical facility explosion and fire.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) found that employees working at a KMCO chemical facility put themselves in harm’s way because their roles during an emergency weren’t properly limited by the company.
Break in piping leads to 10,000-pound isobutylene release
On April 2, 2019, KMCO operations staff were making a batch of sulfurized isobutylene at its Crosby, Texas facility.
At 10:41 a.m., a fist-sized piece of metal broke away from the body of a cast-iron strainer in the batch reactor’s liquid isobutylene supply piping. A field operator trainee who was walking near the piping heard the loud noise that the break caused and immediately contacted his board operator.
This began a series of urgent communications and quick actions taken by the field operator, several board operators and their operations supervisors to stop the flammable isobutylene release, move other employees to safety and prevent ignition of the vapor cloud. The facility’s HAZWOPER-trained emergency response team was notified of the incident at this time.
The operators and supervisors successfully moved workers out of the immediate area and prevented vehicle traffic from approaching the vapor cloud, which was the result of a 10,000-pound release. They also opened other valves along the vapor cloud’s route to allow firewater to spray throughout the batch reactor area.
Vapor cloud ignites while regular employees respond to incident
Most of these tasks were complete when the vapor cloud suddenly exploded while two operators were still within it and one shift supervisor was near it. The resulting explosion fatally injured one of the operators and caused serious burn injuries for the other operator and shift supervisor. At least 28 other workers were injured, including five KMCO employees and 23 contract workers.
Portions of the facility were substantially damaged in the explosion and subsequent fires. Local news outlets reported that the explosion shook nearby homes and was heard throughout the surrounding area. Authorities issued a shelter-in-place order that lasted for four hours to residents within a one-mile radius of the blast.
KMCO filed for bankruptcy in May 2020 and the facility was sold to Altivia Oxide Chemicals LLC. Altivia announced that it planned to dismantle KMCO’s sulfurized isobutylene equipment, which it intended to replace with new oxide reaction equipment.
Culture relied on operators taking action before response team
CSB investigators found that KMCO’s emergency response procedures and training contributed to the severity of the incident because employee roles weren’t properly limited. This allowed responding employees to put themselves in danger.
The facility’s culture relied on unit operators taking quick actions to stop a release before the site’s emergency response team assembled, according to the CSB.
These quick actions did help the operators and supervisors get other workers out of danger during the release, but this was at their own peril. CSB investigators found that the company “could have reduced the severity of the … event by establishing clear policies and training its work force to not put themselves in danger at all to urgently stop a chemical release.”
OSHA’s HAZWOPER, or Hazardous Waste Operations and Emergency Response, standard provides the minimum requirements for emergency response operations involving hazardous materials. As the CSB report points out, “Effective emergency response operations prioritize life safety.” That means emergency response procedures and training must clearly communicate which incidents regular employees should respond to and which incidents should be handled by a more qualified emergency response team.
Policies needed to prevent ‘confined space rescue problem’
The reason for this, according to the CSB, is to prevent the “confined space rescue problem” where employees who lack proper training and equipment put themselves in harm’s way by trying to rescue an unresponsive co-worker during a confined space work activity.
In emergency situations, many workers will instinctively want to help injured or imperiled co-workers, putting themselves in danger at the same time. Again, confined space fatalities are a good example of this. There’s a high incidence of double fatalities in confined space incidents because one worker collapses from the hazard and shortly afterward a co-worker also collapses while attempting to rescue the first victim.
This can be mitigated with policies and training that say something like, “Do not attempt to take offensive actions such as (list whatever actions they shouldn’t take) during this type of emergency.” This policy should then be clearly communicated to all employees and reinforced through training or other periodic communications.
The main lesson here is that emergency response plans, procedures and training must clearly distinguish between incidents regular employees should respond to and those than require a response from a qualified emergency response team.