Paula Kaufmann, CIH
National Public Radio (NPR) recently reported their findings of an investigation of safety issues at the Upper Big Branch mine in West Virginia. I was listening to the report while enjoying my morning walk in a nearby park. It stopped me in my tracks!
As part of their investigative report, NPR discovered that there were situations at the mine when the methane gas monitors on continuous mining machines were disabled because the monitors repeatedly shut down the machines. The miners interviewed explained that supervisors told them it was acceptable to disable these monitors as long as the miner operating the equipment used a hand-held methane monitor to test the air. This is the part of the report that stopped me in my tracks!!!
The methane gas monitors are an essential part of the mining machines fail-safe system. They are factory-installed and essential components of the machine design; when the monitor senses an explosive atmosphere, the mining machine shuts down automatically. The ONLY reason that spark-generating equipment can be operated in an environment likely to contain explosive concentrations of methane gas is precisely because the equipment is designed to automatically shut down if an explosive atmosphere is encountered.
The procedures followed at the mine undermined (no pun intended) a fundamental safety feature of the continuous mining machine.
The problem with using a hand-held monitor as a substitute for the interlock monitor is that the miner operating a continuous mining machine is 25 to 30 feet behind the face of a machine that is a continuous source of ignition (lots of sparks from metal cutting coal and rocks). The monitor must be located directly at the source of the spark. The miner isnt at the source.
How could the mine leadership eliminate a critical risk management feature? When deciding to override a critical safety system, the mine leadership should have considered the potential for loss of life AND damage to the mine AND damage to operating equipment. You have to wonder if anyone really thought about what if? especially as Upper Big Branch was a notoriously gassy (methane producing) and, therefore, dangerous mine. I wonder if any hazard or risk analyses were ever conducted for operating the mining machine without an operational methane monitor. For clarity here is a brief explanation about the hazards and risks of overriding a safety critical system and the outcome of their analyses:
Whats the difference between hazard and risk?
- A hazard is the source of potential damage, harm or adverse health effects on something or someone (i.e., explosive concentration level of methane gas, source of ignition).
- A risk is the chance or probability that damage, harm or adverse health effect will occur if something or someone is exposed to a hazard (i.e., a chance of the methane gas concentration would reach explosive levels in the presence of a source of ignition).
A risk assessment is the process where one
- Identifies hazards,
- Evaluates the risk associated with that hazard, and
- Determines appropriate ways to eliminate or control the hazard.
- Safety controls minimize the risk by controlling the hazard (i.e., shutting down the mining machine eliminates the source of ignition)
Managers must understand the risk and the systems that put in place to control the hazard. This is managing the risk.
At the Upper Big Branch mine, the life-saving interlock system in a known high risk environment was disabled while workers were assured that an inappropriately-located substitute would be effective and work continued without interruption. It appears that appropriate risk management was not the goal since the presence of combustible concentrations of methane gas at sources of ignition might not be detected using the hand held monitors.
The integrity of an organization depends on a leadership commitment to understanding and managing risk to protect their employees and assets as well as their reputation. This NPR report highlights what can happen when leadership is focused on one measure of success, in this case, production. Another recent example of compromised risk in exchange for uninterrupted production is the BP oil leak. Have you ever encountered myopic leadership in your workplace that trades risk management for another benefit. What happened? How do employees feel?