Like a small tremor on the San Andreas fault line of the West Coast as a precursor to the big one, the recent explosion at the ethanol plant in Hastings, Nebraska
provides a similar warning. In less than a year over a dozen combustible dust related fires and explosions have occurred at ethanol facilities throughout the Midwest. The importance of donning proper PPE such as flame resistant clothing (FRC) in such a work environment takes on added dimension with now learning the workers T-shirts were set on
fire from the blast. A week prior to the Hastings explosion, according to media accounts, an ethanol plant in Casselton, North Dakota
experienced a minor fire in the dust collection bin.
Ethanol plants have complex explosion and fire hazards not found in other manufacturing national industries (NAICS) where the attributes of a grain handling facility is combined with a chemical plant in the production of ethyl alcohol. Subsequently, these process facilities must follow stringent regulatory guidelines according to the OSHA Process Safety Management Standard (PSM) and EPA Risk Management Program (RMP). Additionally, combustible dust hazards are addressed in the OSHA Grain Facility Standard.
The confusing aspect of identifying in which area OSHA regulates this national industry besides the OSHA PSM standard is that SIC 2046 for Wet Corn Milling and SIC 2869 for Ethyl Alcohol Manufacturing is not listed as SIC's regulated in the OSHA Grain Facility Standard.
In contrast, NAICS 311221 Wet Corn Milling is listed as a D-1 NAICS in the OSHA Dust NEP.
With the multitude of regulatory control measures protecting workers, the environment, and the public; accidents still happen. The question arises can the current high incident rate be minimized? In less than a year six ethanol plant explosions have occurred in Michigan, Arizona Minnesota, Kansas, Wisconsin, and Nebraska with ensuing injuries in 50% of these incidents.
So what is an unacceptable accident and injury rate before stakeholders reassess current administrative and best engineering control measures? All the proper administrative and best engineering control measures seem to be in place in the prevention and mitigation of fires and explosions. Yet the incidents are exponentially higher than any other national industry(NAICS) in the manufacturing sector. Hazard awareness through a multitude of educational programs is an excellent measure in addressing this issue.
For instance, ethanol trade associations such as the Renewable Fuel Association
(RFA) has an proactive safety program addressing many of the hazards in ethanol production. Additionally, the RFA works collectively with the University of Illinois Fire Service in providing industry with educational programs that prevent future incidents.
Recently, Kirkwood Community College
in Cedar Rapids, Iowa was awarded a $174,978 OSHA Susan Harwood Training Grant in hosting a 2 ½-hour awareness-level combustible dust safety course addressing grain dust and other organic dusts such as sugar, flour and paper. The training will provide 150 courses in 14 Midwestern states for 3,000 employers and employees primarily in the agriculture, food processing and fiber sectors with a focus on grain elevators and ethanol bio-refineries. Training is a great administrative approach in providing hazard awareness. But what about the current best engineering control measures and are they adequate?
With the current progression of incidents, this unique national industry with a primary NAICS 325193 Ethyl Alcohol Manufacturing and secondary NAICS 311211 Wet Corn Milling is quite similiar to tectonic plates shifting, one upon the other, and its only a matter of time before another event occurs in the seismic proportion of the 2007 Steamboat, Iowa explosion, causing millions of dollars in damage in addition to potential fatalities and injuries.
Overall, in the majority of these recent ethanol plant incidents, life safety, structural integrity and mission continuity objectives of the NFPA combustible dust standards have been maintained. This is an excellent example illustrating that combustible dust related explosions cannot be totally prevented only the severity reduced. The task now is to somehow reduce the probability.
This overview is not meant to place blame on the ethanol industry which is actively striving to reduce incident rates. Hopefully the information from tracking and researching these incidents will provide stakeholders an enhanced awareness concerning trends that have been developing. With this information possible preventative and mitigative strategies can be devised in minimizing the occurrence of another tremor.
Incident Google Map
Dry Mill Ethanol Industry .pdf
ETHANOL DRY MILLING: MODEL DESCRIPTION
Feed and Grain Products .pdf