Last week I ran into a contractor who was repairing concrete using a 2 part epoxy in a water reservoir. He had a traditional 4 gas monitor operating inside and was wearing particulate respirators for the dust (silica) hazard. However nothing was protecting the workers from the ethylene glycol, one of the main components in both parts of the epoxy. The lack of knowledge (both the supervisor and the Attendant) regarding the ethylene glycol translated into no protection from the acid gases released during the mixing and curing process.
The crew learned four things that day. First, was that O2, CO, H2S and LEL sensors do not detect ethylene glycol. The supervisor thought that entering another chemical (like ethylene glycol) into the atmosphere would create an O2 deficiency condition. I explained to him that you would have to have 60,000 ppm of ethylene glycol in the space (well over the lethal level of most substances) to get the O2 to drop enough for the monitor to go into alarm. Second, colour changing tube detectors are used to detect ethylene glycol vapours on site. Third, that when the NIOSH pocket guide refers to an “amine odor” it means a product that smells like ammonia. Lastly, they now know that they should use combination acid gas and particulate filters with their respirators.
But the learning didn’t just stop there. My take away from the incident was that no one in the crew had any idea what the word “amine” meant. Had they been able to connect the dots to acid gas, perhaps they would have at least worn the right respirator. Perhaps they also would have reconsidered their gas monitoring choices. I think this goes back to our WHMIS/Hazcom education. We’re really good at teaching WHMIS/Control Product regulations, labeling, and the sections of Material Safety Data Sheets, but how good is our chemistry instruction? Are we truly conducting workplace specific training on the products at our worksite? Yes, some companies deal with hundreds, if not thousands of products, however each employee may deal with only a dozen. Do we have a plan to ensure our workers are sufficiently educated regarding the materials they are handling? Are supervisors encouraged to build safety talks around the substances in their departments? Although there were many contributing causes, I believe that incomplete WHMIS training was the root cause of this potential incident.
So, my To Do List now includes revamping my WHMIS program to ensure we build chemistry instruction into the class. I know my main stumbling block will be to make it “stick” with my students. If anyone has any ideas, let me know.