Gauging Green Disinfection Methods For Healthcare
The best options for reducing or destroying undesirable microbes and ensuring safety in the healthcare environment.
Healthcare facilities across the nation continue to try to strike a balance between environmental disinfectants that are effective in reducing or destroying undesirable microbes, while ensuring patient and employee safety and protecting furnishings and surfaces.
This article takes an objective look at chemical disinfectants and non-chemical disinfecting systems, their “greenness,” benefits, risk factors and safety considerations.
Characteristics of the ideal room disinfection system are:
- Highest possible kill of all relevant organisms, especially Clostridium difficile (C. diff) spores
- Simple to perform
- Cost effective
- Non-consumptive, sustainable
- Can be safely deployed
- No environmental residue
- Reduces incidence of healthcare infections
- High-quality supportive scientific evidence.
Approaches To Greener Disinfecting
Today, the four most common products or equipment types used to reduce the presence of pathogens in the healthcare environment include:
- Chemical disinfectants
- Ultraviolet room disinfecting systems
- Steam vapor sanitation systems
- Disinfecting foggers.
Below is a description of each product as well as advantages and disadvantages a facility manager or business service contractor (BSC) should consider.
These products typically include ingredients such as volatile organic compounds (VOCs), glycol ethers, quaternary ammoniums (quats), phenols, ethanolamine, chlorine compounds, ammonia and sodium chlorides (e.g., bleach).
All of these cleaning compounds are considered hazardous; some are registered as pesticides.
They usually require storage in locked rooms or cabinets, and caution must be taken not to allow these chemicals to come into contact with other chemicals that are not compatible.
These chemicals each come with material safety data sheets (MSDS) and may require specific actions to be taken for spill cleanup and product disposal.
- Easy to obtain
- Easy to train staff in the use of these products
- Relatively inexpensive upfront compared to other products or systems
- Most chemicals can be purchased in concentrated form and dispensed through closed dilution systems
- Some products are pH-neutral and in proper use dilution do not leave a film on the floor
- A few of the products — chlorine compounds and sodium chlorides — are effective in killing all microorganisms when used as directed.
- Chemical disinfectants are generally not good cleaners, and gross matter must be removed first before the disinfectant can effectively kill germs
- All U.S. Environmental Protection Agency (EPA) registered products are labeled as pesticides and require special handling, storage, use and cleanup
- Some products are not effective against blood serum, hepatitis, tuberculosis and other hard to kill bacteria
- Inhalation or exposure may cause respiratory distress, chemical sensitivity and skin dermatitis on certain individuals
- Ensuring proper use, such as proper dilution and dwell time, is challenging.
Ultraviolet Room Disinfecting Systems
These systems use ultraviolet light (UV) to provide broad coverage in a closed environment, such as a patient room or an operating room.
- Reliable biocide activity against a wide range of pathogens
- Surfaces and equipment decontaminated
- The system is quiet in use
- Low energy consumption
- Room decontamination is rapid (approximately 15 minutes) for vegetative bacteria
- Heating, ventilation and air conditioning (HVAC) system does not need to be disabled and room does not need to be sealed
- UV is residue-free and does not give rise to common environmental health and safety concerns
- No consumable products, so operating costs are low' the key cost is acquisition.
- UV emitters contain glass and mercury
- No studies evaluating whether use reduces hospital-acquired infections (HAIs)
- Can only be done for terminal disinfection (i.e., not daily cleaning)
- All patients and staff must be absent from the room
- Substantial capital equipment costs
- Does not remove dirt, dust, blood or body fluids, which would require manual removal
- Sensitive use parameters (e.g., UV dose delivered)
- Does not work in shadows.
Steam Vapor Sanitation Systems
These systems use tap water and a cleaning cloth to capture dirt and other matter during the cleaning and sanitizing process.
Units equipped with water treatment modules and low-moisture (6 percent) saturated steam that is hotter than other types often make disinfecting claims.
- Low contact time of saturated steam required to kill most pathogens — methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) in two to three seconds with units making disinfecting claims
- Thoroughly tested by some manufacturers, peer-reviewed data available
- Moist heat as the functional agent outperforms most traditional chemical cleaning methods
- Non-toxic and only needs tap water and a microfiber or cotton cleaning cloth
- Non-consumptive, petroleum and chemical-free
- Inexpensive to operate, uses only electricity and tap water
- Quiet, no internal moving parts except directed steam
- Training on the use of the equipment is fairly simple
- Does not add a training compliance burden under the UN’s Globally Harmonized System of Classification and Labeling of Chemicals (GHS) because it is non-toxic and no MSDS is needed
- Mobile, wheeled carts that require no lifting
- Dry (6 percent) saturated steam provides rapid kill and penetrates vertical and horizontal surface pores that a cleaning cloth or wipe cannot
- Potential effectiveness on textiles (e.g., privacy curtains) due to penetration
- Reduces cross-contamination because saturated steam kills applicator germs
- Can replace chemical modalities many hospitals have in place.
- The system uses a microfiber cloth that must come into contact with surfaces
- Steam can damage some surfaces and cause operator scalding if equipment is not used per instructions
- Multiple units and storage are needed to outfit each employee
- Proper use and training is important for efficacy.
The foggers dispense a mist of disinfectant throughout the room.
- The fog mist covers and penetrates all items within the patient room
- Complete room coverage can be achieved in a relatively short period of time
- A variety of germicidal solutions can be dispensed through the system.
- Requires personal protective equipment (PPE)
- Fogging does not remove soiling, blood or body fluids. Cleaning is still required
- Moisture may leave condensation on windows in a patient’s room
- According to the U.S. Centers for Disease Control and Prevention (CDC) 2008 Guideline for Disinfection and Sterilization in Healthcare Facilities, this technique of spraying of disinfectants is an unsatisfactory method of decontaminating air and surfaces and is not recommended for general infection control in routine patient-care areas
- Disinfectant fogging is rarely, if ever, used in U.S. healthcare facilities for air and surface disinfection in patient-care areas.
Optimum Qualities Of Surface Disinfecting Systems
To find the best solution for a facility's disinfection, keep the following qualities in mind during the selection process. Systems should have these traits:
- Easy to use
- Disinfect quickly (three to five seconds)
- Kill a broad range of pathogens without “gaps” in the efficacy spectrum
- Reduce potential for cross-contamination of adjacent surfaces
- Non-toxic, non-chemical and sustainable
- Psychologically acceptable to use around patients
- No health risk to sensitive populations such as asthmatics, patients with chemical sensitivities, etc.
- Frequent use will not damage surfaces
- Effective on three-dimensional, vertical and porous surfaces
- Safe for cleaning staff, even for long-term use
- Peer-reviewed efficacy.
- Rutala WA (editor). Disinfection, Sterilization, and Antisepsis: Principles, Practices, Current Issues, New Research, and New Technology. Association for Professionals in Infection Control and Epidemiology, Washington, DC. 2010
- Rutala WA, Weber DJ, HICPAC. 2008. CDC guideline for disinfection and sterilization in healthcare facilities.
- Dr. Benjamin Tanner - Principal of Antimicrobial Test Laboratories
- American Journal of Infection Control
- Cleaning & Maintenance Management
- Dick Zoutman, MD, FRCPC, Emeritus Professor — Medical Microbiology & Infectious Diseases — Queen’s University
- CDC’s 2008 Guideline for Disinfection and Sterilization in Healthcare Facilities
Carl Solomon Sr. is director of hospitality services, UC San Francisco (UCSF) Medical Centers at Parnassus, Mount Zion and Mission Bay (opening February of 2015). UCSF is a 655-bed specialty care teaching medical center, and is ranked #7 of the best hospitals in the nation by U.S. News & World Report. He manages a support services department providing patient transportation, housekeeping, storekeeping, dispatching and waste stream management.
A New Metric
One of the ways antimicrobial products are misrepresented is when purveyors make claims such as “kills 99.9 percent of germs” while not providing the time required for this to occur.
Ideally, request the ratio of germ kill to allotted time resulting in a new metric or number.
Using this ratio, a user can create the Disinfection Performance Indicator (DPI).
This DPI metric, if accepted, would aid healthcare professionals in separating products that are very effective in a short time frame from those that are not.