Nancy Pearce

Seven workers die in Confined Space Accident at Corona Brewery

Blog Post created by Nancy Pearce Employee on Jun 21, 2013

Well, my confined space blog may have slowed down a bit in the past couple months due to other ongoing work, but unfortunately the confined space fatalities have not slowed down...

In April, seven workers were killed in a tank that was undergoing maintenance and cleaning at a plant in Mexico City operated by Corona beermaker, Grupo Modelo.  It is believed that four victims were maintenance contractors and three victims were other Modelo employees.   There are few details available on the incident.  It is speculated that the deaths were due to “unspecified toxins” and that the three Modelo employees had entered the tank in an effort to rescue the other four contract employees.   Mexican authorities are reportedly investigating the incident.  

Confined spaces are or should be clearly recognized in the beer industry.  The large numbers of tanks that are entered for maintenance and cleaning, combined with hazardous atmospheres including carbon dioxide produced during fermentation, inert atmospheres, and ammonia from refrigeration systems creates significant confined space entries and hazards.   These incidents do not just happen in foreign countries, and wine makers are also not off the hook when it comes to confined spaces.  A confined space death occurred just two years earlier at Napa California at Ancien wines when a worker was overcome by nitrogen and argon gases inside a tank.  

Workers entering into tanks in the beer and wine industries should be intimately familiar with confined space entry procedures.  Even if contractors were always used to perform confined space entry work, it is unclear why Modelo employees would have entered the tank if they had been trained to recognize the confined space hazard.  The Modelo company has been in operation since 1925 and is the maker of the number 1 imported beer in the United States. 

This confined space incident has the largest loss of life in one entry that I am aware of.  While it is not uncommon to lose 2-3 workers, this incident claimed the lives of 7 workers.  Confined space entry hazards continue to claim lives despite improved recognition of the hazards and despite regulations and guidelines available to prevent such incidents.  

The National Fire Protection Association is developing a Best Practices document for confined space entry. This document will address gaps in existing standards and will be more prescriptive in describing things like how to test the atmosphere in and around confined spaces prior to entry.  The NFPA document is looking to go beyond the minimum standards and to provide those looking to develop a “gold star” confined space entry program with the information they need to do so.  Please email me at for further information and/or leave a comment below for discussion.  I look forward to hearing from you!