The Chain of InfectionPage 5 of 6

3. Controls

Environmental Controls

Environmental control measures also help prevent the transmission of infection. These measures include (CDC, 2007, 2019):

  • Environmental cleaning (housekeeping)
  • Appropriate ventilation
  • Waste management
  • Linens (textiles) and laundry management

Environmental Cleaning (Housekeeping)

Appropriate housekeeping and sanitation practices are essential to reduce the spread of infection, particularly in high-risk areas such as nurseries, operating rooms and intensive care units. The CDC guidelines include the following recommendations:

  • Keep housekeeping surfaces (e.g., floors, walls, tabletops) visibly clean on a regular basis and clean up spills promptly.
  • Do not use disinfectant sprays in patient-care areas.
  • Avoid large-surface cleaning methods that produce mists or aerosols, or disperse dust in patient care areas.
  • Follow proper procedures for effective uses of mops, cloths and solutions.

Appropriate Ventilation

  • Filter incoming air using central or point-of-use high efficiency particulate (HEPA) filters capable of removing 99.97% of particles ≥0.3 µm in diameter.
  • Direct room airflow with the air supply on one side of the room that moves air across the patient bed and out through an exhaust on the opposite side of the room.
  • Ensure positive air pressure in room relative to the corridor (pressure differential of ≥12.5 Pa to ≥2.5 [0.01-in water gauge]).
  • Monitor air pressure daily with visual indicators (e.g., smoke tubes, flutter strips).
  • Ensure well-sealed rooms that prevent infiltration of outside air.
  • Ensure at least 12 air changes per hour.

Waste Management

There are two categories of hospital waste: regulated medical waste and unregulated waste. According to the CDC, most hospital waste is no more infective than ordinary residential waste, nor is there evidence that current hospital waste management practices have caused disease in the community.

Regulated medical waste (“red bag” waste) demands special precautions in handling and disposal. Regulated medical waste includes:

  • Microbiology laboratory waste
  • Pathology and anatomy waste
  • Bulk blood or blood products
  • Sharp items such as used needles or scalpel blades. (CDC, 2007, 2019)

These items require special handling, transport and storage procedures.

CDC recommends the following guidelines:

  • Personnel responsible for waste management need appropriate training in handling and disposal methods in accordance with hospital policy.
  • Waste generated in isolation areas should be handled using the same methods used for regulated waste from other patient-care areas.
  • Disposable syringes with needles, including sterile sharps that are being discarded, scalpel blades, and other sharp items should be disposed of in puncture resistant containers located as close as practical to the point of use.
  • Do not bend, recap, or break used syringe needles before discarding them into a container.
  • Sanitary sewers may be used for safe disposal of blood, suctioned fluids, ground tissues, excretions, and secretions, provided that local sewage discharge requirements are met and that the state has declared this to be an acceptable method of disposal.
  • Store regulated medical wastes awaiting treatment in a properly ventilated area inaccessible to vertebrate pests. Use waste containers that prevent development of noxious odors. (CDC, 2007, 2019)

If treatment options are not available at the site where the waste is generated, transport regulated medical waste in closed, impervious containers to the on-site treatment location or to another facility for treatment as appropriate.

Regulated medical waste must be treated by a method (steam sterilization, incineration, interment, or an alternate treatment technology) approved by the appropriate authority (such as the state, Veterans Administration, or Indian Health Service) before disposal in a sanitary land fill (CDC, 2007, 2019).

Textile and Laundry Management

Textiles and laundry management also can affect transmission of infection. According to the CDC, except for soiled textiles from patients in isolation, the risk of actual disease transmission from soiled laundry is negligible. Thus common-sense hygienic practices for handling, processing and storage of textiles are recommended. These practices include:

  • Minimal handling and agitation of soiled laundry to prevent gross microbial contamination of the air, surfaces, and healthcare workers.
  • No sorting or rinsing textiles in the location of use.
  • Bagging or placing soiled textiles in containers at the location where it was used.
  • Labeling or color-coding bags or containers for contaminated waste.
  • If laundry chutes are used:
    • Ensure that laundry bags are closed before tossing the filled bag into the chute.
    • Do not place loose items in the laundry chute.
  • Textiles heavily contaminated with blood or other body fluids should be bagged and transported in a manner that will prevent leakage.
  • Do not use dry cleaning for routine laundering in healthcare facilities.
  • Clean textiles should be handled, transported, and stored by methods that will ensure their cleanliness. (CDC, 2007, 2019)

Note: OSHA guidelines state that employers are responsible for laundering workers’ person protective garments or uniforms that are contaminated with blood or other infectious materials (OSHA, n.d.).

Engineering Controls

Engineering controls include equipment, devices or instruments that remove or isolate a hazard. Work practice controls are modifications in technique that reduce or eliminate the likelihood of exposure by altering the manner in which a task is performed (OSHA, n.d.).

Work Practice Controls

Support and protection of the host helps prevent the spread of infection, not only from healthcare worker to patient but from patient to healthcare worker.

Support and protection of the host includes:

  • Vaccination is available to prevent certain conditions, such as Hepatitis B virus.
  • Pre-and post-exposure prophylaxis measures.
  • Protecting skin and immune system integrity of both patients and healthcare workers helps prevent transmission of pathogens.
  • Training and education of healthcare workers in appropriate infection control practices and standards for their particular duties are the foundation of safe patient care. (OSHA, n.d.)