Best Practices for Environmental Infection Prevention and Control

Why it matters

Certain surfaces, especially ones touched frequently—such as light handles, unit switches, and drawer knobs—can serve as reservoirs of microbial contamination. This may cause cross-contamination that can expose dental health care personnel or patients to disease.

Recommendations

Full recommendations on cleaning and disinfecting environmental surfaces can be found on pages 25–28 in CDC's Guidelines for Infection Control in Dental Health-Care Settings—2003 and in the Summary of Infection Prevention Practices in Dental Settings: Basic Expectations for Safe Care.

Types of decontamination

Cleaning removes debris and organic contamination from surfaces. Cleaning is the necessary first step of any disinfection process. If a surface is not cleaned first, the disinfection process can be compromised.

Disinfection eliminates many or all disease-causing microorganisms on an object. However, it does not remove bacterial spores.

Sterilization eliminates all disease-causing microorganisms, as well as bacterial spores. This is typically done by heat (steam autoclave, dry heat, and unsaturated chemical vapor) or liquid chemical sterilants. Sterilization is used for patient care items.

Choosing the right product

The choice of specific cleaning or disinfecting agents is largely a matter of judgment, guided by product label claims and instructions and government regulations.

Choosing the correct product depends on the consideration of multiple factors, including the degree of microbial killing required; the nature and composition of the surface, item, or device to be treated; and the cost, safety, and ease of use.

A single product might not satisfy all disinfection requirements in a given dental facility.

Low-level disinfectants are Environmental Protection Agency (EPA)-registered without a tuberculocidal claim. The label may instead provide a hepatitis B virus (HBV) or HIV label claim. Low-level disinfection kills most vegetative bacteria, some viruses, and some fungi, but cannot be relied on to kill mycobacteria or bacterial spores.

Intermediate-level disinfectants are registered with the US EPA and have a tuberculocidal claim. Intermediate-level disinfection kills bacteria, most viruses and most fungi, but does not reliably kill bacterial spores.

High-level disinfectants, such as glutaraldehyde, are used as chemical sterilants. Because of their toxic nature, high level disinfectants should never be used on environmental surfaces.

Clinical contact surfaces

Clinical contact surfaces, such as light handles, bracket trays, switches on dental units, and computer equipment, are likely be contaminated by direct spray or spatter generated during dental procedures. They can also be contaminated by contact with contaminated gloved hands.

Ideally, clinical contact surfaces, especially those that are hard to clean, should be barrier protected with a Food and Drug Administration (FDA)-approved surface barrier. This barrier should be changed between each patient.

After removing the barrier, examine the surface to make sure it did not become soiled. If it is contaminated, the surface needs to be cleaned and disinfected before the next patient.

If surface barriers cannot be used, clean and then disinfect the surface with an EPA-registered, low-level hospital disinfectant that is effective against HIV and HBV.

If the surface is visibly contaminated with blood or other potentially infectious material, clean and then disinfect the surface with an EPA-registered, intermediate-level hospital disinfectant with a tuberculocidal claim.

Housekeeping surfaces

Housekeeping surfaces, such as floors, walls, and sinks, do not come into contact with patients or devices used in dental procedures. These surfaces have a limited risk of disease transmission and can be decontaminated with less rigorous methods than those used on dental patient-care items and clinical contact surfaces.

Housekeeping surface can be cleaned with soap and water or cleaned and disinfected if visibly contaminated with blood.

Reusable mops and cloths should be cleaned after use and allowed to dry before reuse. Alternatively, use single-use disposable options.

Prepare fresh cleaning and disinfecting solutions daily and according to the manufacturer's recommendations.

Disposing of medical waste

The majority of soiled items in dental offices are general medical waste. Examples include used gloves, masks, gowns, and lightly soiled gauze or cotton rolls. Non-regulated medical waste can be disposed of with ordinary waste.

Some waste—such as gauze soaked in blood, extracted teeth, and used needles—carries a substantial risk of causing infection during handling and disposal and is regulated medical waste. This type of waste requires special storage, handling, neutralization, and disposal strategies.

Regulated medical waste that does not have any sharp items can be contained in a single leak-resistant biohazard bag.

Sharp items, like scalpel blades, needles, or syringes, should be placed in puncture-resistant containers with a biohazard label (e.g., a sharps container).

Any facility generating regulated medical waste should have a plan for its management that complies with federal, state, and local regulations.

Dental health care facilities should dispose of medical waste regularly so that it does not accumulate.

Frequently asked questions

Who regulates disinfectants?

EPA regulates low- and intermediate-level disinfectants that are used on environmental surfaces (clinical contact surfaces and housekeeping). FDA regulates liquid chemical sterilants/high-level disinfectants (e.g., glutaraldehyde, hydrogen peroxide, and peracetic acid) used on heat-sensitive semicritical patient care devices.

Does CDC recommend a specific environmental surface disinfectant?

CDC does not test, evaluate, or otherwise recommend specific chemical germicides. The CDC dental guidelines provide overall guidance for dental health care personnel to choose from among general classes of products based on infection prevention and control principles. This guidance recommends appropriate application of liquid chemical disinfectants registered with the EPA for use in dental health care settings.

The EPA maintains a list of selected EPA-registered disinfectants.

Since tuberculosis is not transmitted by contaminated environmental surfaces, why is it important to select a disinfectant with tuberculocidal claim?

The ability to kill Mycobacterium tuberculosis is used as a benchmark to measure how well a disinfectant can kill germs. Mycobacteria have among the highest levels of resistance of all microorganisms. Therefore, any germicide with a tuberculocidal claim is considered capable of inactivating a broad spectrum of pathogens, including less resistant organisms such as bloodborne pathogens (e.g., hepatitis B and C viruses, HIV). The use of such products on environmental surfaces plays no role in preventing the spread of tuberculosis (which is airborne).