ANTIMICROBIAL MATERIALS AND SURFACES

Both airborne and waterborne transfer of germs and bacteria are of great concern in health-care settings. However, infectious organisms can also be transferred indirectly through our hands. When an infected person touches a wall, curtain, door handle, or piece of equipment, they may deposit bacteria on that surface. A healthy person may come into contact with the infectious bacteria when they touch the same surface. From there, the bacteria may be transferred to something the non-infected person eats or drinks, or it may enter the body when that person rubs their eyes or nose.

Frequent handwashing is often promoted as the best way to protect against infection; however, this practice requires constant diligence and access to handwashing facilities. Hence, finding ways to control or eliminate the spread of diseases is an increasing priority in hospital settings as well as other high-occupancy buildings, particularly where vulnerable populations may be present. These include retirement communities, assisted living facilities, spa/wellness centers, schools, and other public buildings.

One way to combat the transmission of these diseases is to reduce the amount of time that bacteria or viruses can survive on surfaces that people touch. This can be accomplished by specifying antimicrobial materials and products.

The term “antimicrobial” is used to generically describe materials or products that have been shown through testing to kill or stop the growth of bacteria and other microorganisms. Specifying materials with antimicrobial properties for touchable surfaces is a prime strategy for stopping or slowing the spread of disease-carrying germs in health-care facilities.

Copper-Clad Wire Fabric

Copper-clad wire fabric is an innovative product that can be incorporated into building interiors as part of an overall design scheme and for its demonstrated antimicrobial properties. This fabric consists of pure copper metallurgically bonded to the surface of low-carbon steel wire. It is extremely durable and contributes a distinct and beautiful aesthetic. Copper-clad wire exhibits a brilliant red polished finish when extruded in a continuous solid-cladding process. However, if left bare and untreated, the wire’s appearance will evolve over time, taking on brownish hues and ultimately a grey-green patina. Left in its natural form, copper-clad steel wire is naturally antimicrobial and can enhance public safety where it is installed. (Applying a thin layer of clear automotive lacquer can help maintain the bright salmon color; however, this finish may reduce the material’s antimicrobial effects.) Copper-clad wire conforms to ASTM standards for both interior and exterior applications and is available in a wide variety of wire gauges.

Antimicrobial Properties of Copper

Copper, whether in pure form or in an alloy such as brass, bronze, or copper-nickel alloy, naturally has antimicrobial properties. For millennia, these metals have been attributed with reducing illness, although our understanding of germs and bacteria as the cause of such illnesses is a much more recent development.

The scientific research on the antimicrobial effects of copper suggests that it affects bacteria in two sequential steps. First, the copper surface directly interacts with the outer membrane of the bacteria cell, causing the membrane to rupture. Once ruptured, the cell loses vital nutrients and water, causing a general weakening of the cell and finally killing off the bacteria altogether.

Antimicrobial products marketed and sold in the United States are regulated by the EPA to ensure the products are safe to use. Advertising claims about protecting public health and efficacy against specific pathogens must be supported by rigorous testing under EPA-approved protocols. For example, a product or material must demonstrate that it continuously kills more than 99.9 percent of bacteria within 2 hours of contact between routine cleanings. Copper alloy materials are registered by EPA (Reg. Nos. 82012-1 to 6) to make public health claims against six specific bacteria:

• E. coli O157: H7, a food-borne pathogen that has been associated with large-scale food recalls;
• Methicillin-Resistant Staphylococcus aureus (MRSA), one of the most virulent strains of antibiotic-resistant bacteria and a common culprit of hospital- and community-acquired infections;
• Staphylococcus aureus, the most common of all bacterial staphylococcus (i.e., staph) infections that can cause life-threatening diseases, including pneumonia and meningitis;
• Vancomycin-resistant Enterococcus faecalis (VRE), an antibiotic-resistant organism responsible for 4 percent of all HAIs;
• Enterobacter aerogenes, a pathogenic bacterium commonly found in hospitals that causes opportunistic skin infections and impacts other body tissues;
• Pseudomonas aeruginosa, a bacterium that infects the pulmonary tracts, urinary tracts, blood, and skin of immune-compromised individuals.

While copper has been shown to be very effective at killing these six specific bacteria, it should be noted that at this time, there is very limited information and testing available on COVID-19 or other similar coronavirus microbes.

Photo courtesy of Cascade Architectural

Copper is naturally antimicrobial and, where used, may help reduce the transmission of certain pathogens from surfaces.

Hygienic Privacy Curtains

Privacy curtains are essential for protecting the privacy and dignity of patients in health-care settings. They are used in emergency departments, private rooms, and elsewhere, and are an essential tool for rapidly reconfiguring a space. The selection of colors and textures can help create a warm and welcoming environment for patients, residents, visitors, and staff. However, these fabric curtains are also a prime vector for contamination, as they are touched frequently by many different people. They also require laundering, unlike counters or medical devices.

Although frequent changing and washing of these curtains can help reduce the incidence of cross contamination, as can practicing good hand hygiene, the risk cannot be completely eliminated.

Selecting easy-to-clean fabrics with antimicrobial properties can reduce the risk further. Fabrics that utilize silane-based technology have been tested and proven to be permanently antimicrobial and inhibit the growth of mold and mildew. These fabrics also repel liquids and are highly resistant to most stains. These properties make them ideal for cubicle curtains, shower curtains, and window treatments.

One hospital in New York did a room turnaround analysis and determined that by using antimicrobial fabric curtains, they could speed the changeover and save the hospital $50,000 in the first year and $140,000 in each subsequent year. The savings derived from lower laundering costs, change-out time, and reduced loss in revenue due to room closures.

Another option that utilizes the same antimicrobial fabric is snap-panel curtains, which allow easy change-out of only the soiled panels. Standard panel sizes are 66 inches wide by 66 inches high; custom sizes are available. These panels easily snap into place and can be configured to any length. No ladder is needed, which reduces the risk of strains and falls.

There are some cases where disposable curtains might be the best options. These are typically made from 100 percent woven polypropylene and include a polyester mesh and Velcro tie back. Be sure to select disposable curtains that have passed the NFPA 701 Fire Retardant Test.

Analysis shows that disposable privacy curtains over time can cost as much as 70 percent more than washable curtains. However, disposable curtains may be a better alternative in spaces where frequent change-outs are the norm. Environmental services and maintenance staff must weigh their options when it comes to privacy curtains. They may switch to disposable curtains, stay with washable curtains, or employ a mixed strategy and utilize disposable curtains for some applications and washable curtains for others.