Copper vs Brass: Which Metal is Superior for Killing Germs and Viruses?

When it comes to antimicrobial properties, copper has long been recognized as one of the most effective materials in eliminating bacteria and viruses. In comparison, brass, a copper-zinc alloy, while still possesses some antimicrobial benefits, is often less effective than pure copper.

Understanding Antimicrobial Properties

Copper exhibits a strong antimicrobial activity, often killing bacteria and viruses on contact within minutes. This effectiveness arises from copper's ability to disrupt the cellular processes of microbes, leading to their rapid death. Numerous studies have confirmed that copper surfaces can significantly reduce microbial load, making them particularly effective in healthcare settings to prevent the spread of infections.

Brass, on the other hand, is an alloy primarily composed of copper and zinc. While it does exhibit some antimicrobial properties, these are generally less pronounced and less immediate than those of pure copper. The presence of zinc can reduce the overall antimicrobial effectiveness. Therefore, while brass can contribute to hygiene, its performance is typically inferior to that of copper.

Research Findings and Applications

A growing body of research supports the use of copper in various applications to combat microbial growth. Surfaces made of copper have been shown to reduce microbial load significantly, making them highly effective in healthcare settings where the prevention of infection spread is critical. Brass, although having some antimicrobial effects, is often not as fast-acting or as effective as copper.

Considering its antimicrobial properties, copper is commonly used in high-touch surfaces like doorknobs, faucets, and hospital equipment. This application helps reduce the spread of infection through frequent contact. Meanwhile, brass is utilized in a variety of other applications, with copper being the preferred choice for its superior antimicrobial performance.

A Personal Anecdote: Copper Doorknobs in Healthcare

Back in the mid-2000s, a manufacturer of ironmongery products, based in Birmingham, sought to market copper and copper-zinc alloy doorknobs to the National Health Service (NHS) and healthcare settings. They faced significant resistance because of the required maintenance: the NHS wanted door handles that would look 'clean' and hypothesized that regular hand polishing would be labor-intensive and impractical for their needs.

However, copper doorknobs and other copper-based hardware have several advantages. Besides being highly antimicrobial, they are durable, resistant to corrosion, and aesthetically pleasing. These qualities, combined with their rapid bacterial and viral elimination properties, make them an ideal choice for high-touch surfaces in care homes and healthcare facilities.

After several discussions and demonstrations, a care home provider recognized the benefits of copper doorknobs. Today, they have become standard practice in all their properties, reducing the transmission of Legionnaires' disease, avian flu, swine flu, and other zoonotic influenza viruses, as well as SARS.

In conclusion, if the goal is to effectively kill germs and viruses, copper is the superior choice, compared to brass for both individual applications and broader public health measures.