Closed System Technology Drives the Trend Toward Safer Dispensing of High-Purity Chemicals
- Created: Friday, 01 October 2010
In dozens of industries and in millions of applications around the world, dangerous chemicals are transferred from their original shipping containers into smaller jugs or buckets, or applied to other end-use processes. Historically, the predominant dispensing method in many of these applications has been through an open system where the liquid is poured out of the container. In many industries using high-purity chemicals, a popular dispensing method is a semi-closed system that pumps the liquid out of a drum or container. In these systems, a dip-tube draws chemicals from vertically oriented containers using an attachable hand or electric pump. While a step in the right direction, the semi-closed dispensing system requires a dip-tube that needs to be removed and re-inserted each time a new drum is used, exposing the end user to drips, leaks, and fumes during transfer. The primary drawback of all open and semi-closed systems is that they needlessly expose the user, equipment, and the environment to potentially hazardous chemicals and vapors.
The Occupational Safety & Health Administration (OSHA), along with other health and safety organizations, is taking aggressive steps to minimize the risk of personnel and the environment being exposed to chemicals. These increased environmental and safety concerns are driving the trend toward disposable systems that require chemicals to be transported from container to point of use in a closed manner. At the same time, chemical packagers and end-users — well-aware of the liabilities involved — are increasingly looking to incorporate closed systems into their chemical management solutions, both in hazardous and non-hazardous industries.
The semiconductor and life sciences industries were among the first to implement completely closed systems, not only to minimize the risk of workforce chemical exposure, but also to prevent contaminants from getting into their chemicals. With highly sensitive manufacturing processes, the presence of even the smallest amount of dirt or foreign material can prove extremely costly. A closed system allows them to control chemical purity from the point of origin to the point of use.
Another key driver is simply the high cost of open systems, including expenses related to cleanup, wasted product, and accidents or injuries. For example, long-term exposure to some chemicals can cause workers to become sick, resulting in an increase in worker compensation claims. Additionally, companies might be able to reduce their insurance premiums if they can show their insurer that a closed system minimizes chemical exposure and improves overall plant safety.
For chemical and packaging industries that need to transfer, protect, and use hazardous materials in their manufacturing processes, a closed system is the safest and presents the least risk of exposure. Moreover, in the case of a facility using high-purity chemicals in their processes, a closed system can help prevent particle contamination. While the applications for closed systems vary widely — from benign materials to highly dangerous liquids such as sulfuric acid — the overall objective is the same: to enclose the product and to protect it against oxygen and particle contamination while protecting the environment and personnel who must handle the containers. This includes minimizing or completely eliminating the potential for chemical or vapor exposure at the point of connection, during dispensing, and when the container is disconnected.
In many semi-closed, top-dispensing systems, the biggest source of chemical exposure is from the constant reuse of the “stinger” type dip-tube, which exposes the user to drips, leaks, and fumes during transfer. The best way to minimize this exposure is to limit the need to remove the dip-tube from the drum. This is accomplished with containers that have an integrated dip-tube-based dispensing system that includes a common bung closure, a disposable diptube, and a reusable quick disconnect coupler. This ensures that both ends of the dispensing system are sealed from the point of origin to the point of use. To dispense the chemical, the user simply removes a shipping plug and then connects the coupler. The end user doesn’t have to worry about moving diptubes in and out of drums or opening the container in any significant way.