Protect Yourself and Your Employees by Finding the Right Caps for Your Chemical Bottles


It's common for bottles to over-pressurize, break and spill in labs causing emergency response situations, endangering employees and costing organizations money. Even plastic or cardboard containers and bottles can become bloated and unstable, creating a safety hazard. If you've ever had a puffed up bottle or a shattered glass container in your lab, it might be time to start thinking about using your bottle caps as an added safety measure. 

Burst or puffed up bottles and containers are caused by chemicals mixing, evaporating, or reacting in such a way that a gas is released, causing pressure to build up and potentially break the container. This type of reaction is most common with oxidizers (like hydrogen peroxide), mixing inorganic acids with organics, Piranha Etch, and Aqua Regia solutions.

This problem is similar to the issue of boiler pressure seen in many industrial settings. The solution for boiler pressure, then, is a relief valve, or a way to equalize the pressure inside and outside of the boiler. In a similar way, chemical bottles that are in danger of bursting need a way to equalize their pressure with the surrounding environment, and the best way to do this is to start from the top by using specialty container caps. Here are two commonly used caps specifically designed to control pressure inside chemical storage bottles. 

Cap Types

Circumvent caps allow free passage of a gas to the top of the cap, where a grooved foam layer and a membrane are located. As the gas passes through the cap, the membrane collects liquids to keep the cap from leaking expensive or dangerous chemicals. The gas then continues to move along the grooves of the foam to the threads of the cap, where it is then allowed to vent in order to relieve internal pressure. Outside air flows back in along the same path, allowing the pressure to equalize and prevent the bottle from rupturing. These three important steps work together to ensure that your chemicals remain safely confined within their bottles without building up any appreciable pressure. 

When used to store chemicals that are not actively reacting, these caps have greatly reduced the occurrence of burst chemical bottles at universities, making these labs safer workplaces for all. 

Airfoil caps have similar characteristics to circumvent caps with the exception that they have a hole in the top which is also lined with the foam and membrane. Therefore, instead of the gas moving along the foam grooves and down the threads of the cap, the gas goes straight up through the foam and membrane and exits at the top of the cap. This allows for the collection and control of effluent gas if necessary, adding yet another layer of safety to your chemical storage. 

Both of these types of caps come in a variety of sizes, making them optimal for a wide variety of bottles as well as other jugs and carboys. Therefore, you don't have to repackage your entire chemical inventory in order to make your lab safer, you simply need to swap out your tops. 

Learn more about how we can help manage your chemical inventory and ensure safety and compliance in the link below.

View Services