“Change can be scary, but you know what’s scarier? Allowing fear to stop you from growing, evolving and progressing.” Mandy Hale
Two months ago, I chose to leave the banking industry after eight years to pursue a career in process safety. I now work alongside engineers who hold degrees from prestigious universities. Their critical thinking skills have been polished and refined. They know what they’re doing, and do it confidently, knowing that they’re making a difference. I was intimidated. Just the same, I didn’t let fear stop me from “growing, evolving, and progressing.” I took the leap and I learned. I took classes, I trained, and I grew. I embraced the change, and the fear, and it was worth it. Now I’m making a difference as well and I love what I do.
It’s Not What I Thought
We’ve all heard about the dangers of mixing two incompatible chemicals. Every housekeeper has been told not to mix cleaning compounds, or else offensive gases are released. If you mix bleach and, honestly, just about anything, you can get gassed. In the bathroom, that means you have to leave, probably gasping for air, and wait for the gas to clear. On an industrial scale, like what recently happened in Atchison, Kansas, you send over a hundred people to the hospital. In the bathroom, the answer is “Don’t do that.” On an industrial scale, nobody has to say “Don’t do that,” but it still happens.
Process safety encompasses far more than I initially assumed. If you’ve been working in the field for a while, it is easy to take for granted the knowledge you have amassed. Conversely, if you haven’t studied in the field, process safety is more than making sure the scientist in the lab coat doesn’t combine two beakers of incompatible chemicals. In fact, a lot of process safety has to do with avoiding something going wrong when using chemicals exactly as intended.
But how else can chemicals be dangerous when involved in a process? Whether you are new to the field or so seasoned that you can take the basics for granted, it’s worth it to step back and look at process safety from a beginner’s perspective. Since beginning my work in process safety, there are three things that have especially caught my attention.
Dust Accumulation
Anything that can burn can explode. The difference between burning and exploding is that an explosion is simply burning that happens all at once. The way to get something that burns to burn all at once is to reduce it to dust. Those fine combustible particles, suspended in air, confined, and ignited, will burn all at once. They’ll explode.
Dusts are created when materials are transported, handled, processed, polished, ground and shaped. Dusts are also created by abrasive blasting, cutting, crushing, mixing, sifting or screening dry materials. The dust accumulates and becomes a combustion hazard. OSHA defines combustible dust as “a dust that can create an explosive atmosphere when it is suspended in air in ignitable concentrations”. Essentially, any workplace that generates combustible dust is potentially at risk. Some workplaces and industries that favor this include grain elevators, food production, chemical manufacturing, woodworking facilities, and metal processing. (Yes, metal processing. If it can oxidize, it can explode if it oxidizes all at once.) Materials that can pose a combustible dust hazard include egg whites, sugar, powdered milk, aluminum, coal, pesticides, rubber, and wood. This list is just the tip of the iceberg. Some of these materials are not normally even thought of as combustible, but they can burn or explode if the particles are the right size and in the right concentration.
When dust is disturbed under certain circumstances, there is the potential for a serious explosion to occur. Any fire needs three elements – fuel, oxygen, and an ignition source. A combustible dust explosion needs those three elements as well as a dispersion of dust particles and confinement of the dust cloud. If the dust is disturbed and the conditions are right, an ignition source as insignificant as a chain dragging on concrete has the potential to spark a combustible dust explosion. Proper housekeeping and control of ignition sources are important safety measures in dust producing environments. Now I know that saw mill down I drive past is not just dirty, but a process safety hazard.
Nitrogen Release
Nitrogen is something we all recognize. Air is about four-fifths nitrogen, so we breathe it constantly. Unlike air, which also contains oxygen, pure nitrogen doesn’t support combustion, so it is widely used commercially and in plants conducting chemical processes. It is important to be aware of the hazards of nitrogen’s use as well as the safety protocols in place to prevent its release.
A nitrogen release is difficult to detect without proper equipment and, in high concentrations, nitrogen is a swift and silent killer. It is a leading cause of death by asphyxiation, the condition in which the body does not receive adequate oxygen to function. Nitrogen displaces oxygen and the resulting oxygen-deficient atmosphere is hazardous to humans. Nitrogen is odorless and tasteless – and it only takes a few breaths to begin to affect the body’s oxygen supply. A few breaths of pure nitrogen exposure may cause unconsciousness and death can occur quickly after that. In fact, nitrogen is so effective at killing that in 2015 Oklahoma became the first state to approve nitrogen gas as an alternative to lethal injection.
When we consider how widely nitrogen is used and how many people are in its presence daily, it is vital that safety managers ensure there are alarms and meters in place to alert of unsafe nitrogen levels. It is important to verify that alarms are in proper working order and that ventilation systems are running effectively.
Runaway Polymerization
Polymerization is a chemical reaction in which many small molecules, called monomers, join to form a large molecule, a polymer. The reaction often produces heat and pressure. It can quickly get out of control since, once started, the reaction is accelerated by the heat that is produced. The uncontrolled buildup of heat and pressure can rupture closed containers, or as a more serious consequence, result in a fire or explosion. There are many substances that can undergo vigorous polymerization by themselves when they are heated or exposed to light.
The dangers of runaway polymerization can be controlled with inhibitors, but inhibitor levels in materials may gradually decrease during storage, even at ideal temperatures. Temperatures too high or too low may have a more drastic effect on the inhibitors, and some inhibitors may require oxygen levels to be monitored in storage. Imagine now, the importance of correct labeling and storage of chemicals in a plant that utilizes these substances or carries out polymerization in their processes.
Learn from Experience (but not necessarily yours)
These hazards give a hint into the dangers associated with process safety, but they only scratch the surface. While the field of process safety is still fresh and new to me, I have learned one thing for sure: while lots of hazards seem obvious once you understand them, there is a lot to learn and a lot to know.
Fortunately for me, I work with a group of process safety professionals that have made this their life’s work, and they are happy to share what they’ve learned with me. There is an old safety slogan: “Don’t learn safety by accident.” Really, there’s no other way to learn safety, but they don’t have to be our accidents. We learn from experience, but it doesn’t have to be our personnel experience. We can, and must, learn from incidents in the past and from the experiences of others.
So Much to Learn, So Much to Teach
If you are new to process safety, take heart. There is a ton to learn, but people are willing to teach you. You just have to be willing to learn from them. Don’t insist on learning from your own mistakes.
On the other hand, if you’ve been around the block so many times you know where all the parking spots are, it’s time to teach the new people what you’ve learned. Your experience is more valuable than you know. These are not secrets you want to protect, but knowledge you want to impart. You learned from others. Now give others the chance to learn from you.
More than very good!!!