Lab Safety Pictograms and Their Meanings, Part 2

In our prior post, we began a series explaining the modern hazard communication pictograms set by OSHA. If they are clearly understood, lab safety pictograms can communicate caution in far less time than a paragraph full of words. In this post, we explain (in the language we know best) the detailed meaning behind the final four of these hazard communication pictograms.

Explosive Hazard

This exploding circle pictogram is fairly clear. You will find this symbol on containers in your lab that hold chemicals with explosive properties. This could mean they are unstable and capable of a reaction that can damage surrounding equipment, dedicated lab furniture, and nearby human beings. It could also mean they are self-reactive, with the potential to explode or cause a fire, even without their coming into contact with air (unlike flammable materials labeled with the flame symbol, which need air in order to combust). One last group of chemicals that could bear this pictogram are organic peroxides.

Oxidizing Agents

The meaning of this pictogram is less obvious, and one reason that we believe regular lab safety refresher trainings are a wise investment. The circle represents an oxidizing material, which readily emits oxygen or another oxidizing substance. The flames indicate that one possible result of this oxidization would be an explosion or the intensification of an existing fire. Even without air, such agents can intensify a fire because of their oxidizing properties. Oxidizing liquids and solids frequently found in labs include nitrates, chlorates, bromine, peroxides and perchloric acid. Any of these may also be toxic or corrosive and should be handled with caution.

Environmental Dangers

While this pictogram is not mandatory according to OSHA, its use is strongly suggested because of the effects these materials can have beyond your lab. While lab safety is our primary concern, the safety of our planet is critically important for the long-term viability of any lab. Substances labeled with this pictogram have the potential to harm people and the planet in significant ways, most often through aquatic contamination.

There are two types of environmental hazards: acute and chronic. Acute hazards will cause toxic effects from a single exposure or episode. Chronic hazards can cause toxicity after prolonged exposure in the environment over time. Such substances should be disposed of properly and never washed down a drain.

Skull and Crossbones

The skull and crossbones is a pictogram many see on a pirate’s flag in childhood. It dates back to the late Middle Ages, where it was frequently used as a memento mori, or reminder of death, on tombstones. Today, this lab safety label clearly indicates the acutely toxic nature of the substance. Acute toxicity means that a single exposure to the chemical in the container is enough to kill someone. Exposure could occur through inhalation, swallowing, or skin contact.

While not every modern pictogram is worth a thousand words, each of these OSHA hazard symbols indicates a clear lab safety hazard. Since the popular meaning of pictures can change or be lost over time (that classic radiation symbol, for example), it’s helpful to regularly be reminded of a lab safety pictograph’s meaning.

We also find it’s helpful to be reminded of the lab safety benefits of dedicated lab furniture. With roughing pump overheat protection built into our IonBench MS, there’s less likelihood of your mass spec accidentally starting a fire if you were to leave a flammable material on or near your IonBench. By suppressing the sound of those roughing pumps, we also make it easier for you to hear the telltale popping sound of something catching fire in your lab.

To learn more about how our lab benches are dedicated to your safety, contact Tim Hawkins via email or at 1-888-669-1233.