Overview

Adequate ventilation can reduce the transmission of infection in health-care settings. Natural ventilation can be one of the effective environmental measures to reduce the risk of spread of infections in health care.

This guideline first defines ventilation and then natural ventilation. It explores the design requirements for natural ventilation in the context of infection control, describing the basic principles of design, construction, operation and maintenance for an effective natural ventilation system to control infection in health-care settings.

Contents

• Foreword
• Acknowledgments
• Contributors
• Conflicts of interest
• Executive summary
• Acronyms and definitions of terms
• Part 1. Infection control and ventilation
  • 1. General principles of infection control
    • 1.1 The concept of isolation precaution and an historical review
    • 1.2 Isolation practices for infection control
    • 1.3 Isolation practices for airborne infections
    • 1.4 Infection control for high-risk procedures
    • 1.5 Summary
  • 2. Concepts and types of ventilation
    • 2.1 Ventilation
    • 2.2 Assessing ventilation performance
    • 2.3 Comparison of mechanical and natural ventilation
    • 2.4 Mechanical versus natural ventilation for infection control
    • 2.5 Summary
  • 3. Infection and ventilation
    • 3.1 The association between ventilation and infection
    • 3.2 Ventilation requirements relating to airborne infection control
    • 3.3 World Health Organization recommendations relating to natural ventilation requirements
    • 3.4 Summary
• Part 2. Designing for natural ventilation
  • 4. Understanding natural ventilation
    • 4.1 The driving forces of natural ventilation
    • 4.2 Ventilation flow rate
    • 4.3 Summary
  • 5. Design and operation
    • 5.1 Designs for natural ventilation and hybrid ventilation systems
    • 5.2 Basic design concepts for natural ventilation
    • 5.3 Climatic and other considerations in ventilation design
    • 5.4 Designing for natural and hybrid ventilation systems
    • 5.5 Types of natural ventilation systems
    • 5.6 Applicability of natural ventilation systems
    • 5.7 Commissioning, operation and maintenance
    • 5.8 Summary
• References
• Annexes
  • Annex A Articles included in the systematic review on the association between ventilation and infection
  • Annex B Recommendation GRADE appraisal tables (GRADE system)
  • Annex C Respiratory droplets
  • Annex D Basic concept of ventilation flow rate
  • Annex E Rationale for determining the minimum ventilation rate requirements
  • Annex F Natural ventilation example I: Hospital Nacional Dos de Mayo, Lima, Peru
  • Annex G Natural ventilation example II: Grantham Hospital, Hong Kong SAR, China
  • Annex H Natural ventilation example III: Tuberculosis Control Unit, Tan Tock Seng Hospital, Singapore
  • Annex I Natural ventilation example IV: IOM Isolation Centre, Damak, Nepal

This document is the product of collaboration between WHO Water Sanitation and Health (WSH) and WHO Biorisk Reduction for Dangerous Pathogens (BDP)

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