From Tuberculosis › Chapter 14: Infection prevention and control · Médecins Sans Frontières, Current online edition, 2026
Ventilation and environmental control measures to reduce airborne TB transmission in health facilities.
- Issuer
- Médecins Sans Frontières
- Edition
- Current online edition, 2026
- Audience
- Health facility managers, TB programme staff, infection prevention and control teams, clinicians
- Evidence
- Expert consensus based on WHO policy
- Reviewed
- 23 Oct 2026 · GMJ
What this guideline says
GMJ summary
This section from the MSF Tuberculosis guideline addresses environmental measures—primarily ventilation and germicidal ultraviolet lamps—to reduce airborne transmission of Mycobacterium tuberculosis in health facilities. Ventilation effectiveness is measured in air changes per hour (ACH), with WHO recommending a minimum of 12 ACH in areas where TB transmission may occur.
The guideline prioritises natural ventilation through strategic building layout, with doors opening to outside corridors and windows directing airflow outwards. When natural ventilation is insufficient, assisted natural ventilation (fans) or mechanical ventilation systems should be employed. Sputum collection areas should be located in open air when possible, or in very well-ventilated indoor rooms (at least 20 ACH).
Laboratory facilities require specific ventilation provisions: ventilated workstations for sputum smear preparation and Xpert cartridge loading when ventilation is below 12 ACH, and biosafety cabinets for all specimen processing involving centrifugation or cutting/grinding regardless of air change rate. Germicidal ultraviolet lamps may supplement ventilation when adequate ACH cannot be achieved.
Key points
For clinicians — doses and thresholds as stated in the guideline
- Minimum 12 air changes per hour (ACH) recommended in all areas where TB transmission may occur (wards, diagnosis rooms, corridors)
- Sputum collection should be performed in open air or in very well-ventilated indoor rooms with at least 20 ACH
- Waiting areas, visiting areas and gathering spaces should be shaded outdoor areas open on at least three sides
- Laboratories with ventilation <12 ACH require ventilated workstations for preparing sputum smears and loading Xpert cartridges
- Biosafety cabinets required in laboratories if specimens are centrifuged or cut/ground, regardless of air change rate
- Natural ventilation should be maximised through building design: doors opening to outside corridors, strategic window placement
- When natural ventilation is insufficient, use fans (assisted natural ventilation) or mechanical ventilation systems
- Germicidal ultraviolet (GUV) lamps should supplement ventilation in high-risk facilities when 12 or 20 ACH cannot be achieved
From the guideline
Verbatim
“WHO recommends a minimum of 12 ACH in areas where TB transmission may occur (wards or rooms, diagnosis rooms, corridors, etc.)”
Editor’s perspective
Why this matters for Georgia and the region
Prof. Giorgi Pkhakadze, MD, MPH, PhD
Editor-in-Chief, Georgian Medical Journal · Chair, Public Health Institute of Georgia · WHO consultant, health and migration
As someone who has worked extensively on TB control in the South Caucasus region, I recognise that environmental infection control remains an underutilised intervention in our health facilities. Many of Georgia's TB facilities, particularly those in older buildings, likely fall short of the 12 ACH minimum standard, yet this is one of the most cost-effective interventions we can implement. I would stress to Georgian clinicians and facility managers the immediate feasibility of relocating sputum collection to outdoor areas—a simple measure requiring minimal investment that can dramatically reduce nosocomial transmission. The realistic caveat for our region is that mechanical ventilation systems, while necessary in some settings, require sustained funding for installation, electricity and maintenance that may compete with other programme priorities; therefore, maximising natural and assisted natural ventilation through building modifications and strategic fan placement should be the first-line approach in most Georgian facilities.
ORCID 0000-0001-7609-4515 · Perspective written for the GMJ Guidelines Library, 23 Oct 2026
Applicability
Georgia and the South Caucasus
Georgia’s National TB Programme, which has made significant progress in recent years, operates numerous TB facilities where these environmental control measures are directly applicable. Health facilities across Georgia and the South Caucasus managing TB patients should audit current ventilation rates against the 12 ACH minimum standard, particularly in older Soviet-era buildings not originally designed for natural ventilation. National programmes would need to assess the feasibility of mechanical ventilation systems in colder climate zones where year-round natural ventilation may be impractical, and consider retrofitting existing facilities with wind-driven roof turbines or assisted ventilation before investing in more expensive mechanical systems. The recommendation for outdoor sputum collection areas is particularly relevant and cost-effective for the region’s climate during most of the year.
Questions this guideline answers
Quick answers
What is the minimum ventilation standard for TB wards and diagnosis rooms?
WHO recommends a minimum of 12 air changes per hour (ACH) in all areas where TB transmission may occur, including wards, diagnosis rooms and corridors. This means the entire volume of air in the room must be replaced at least 12 times every hour.
Where should sputum collection take place?
Sputum collection areas should be located in open air whenever possible. 'Sputum collection booths' similar to voting booths can protect patient privacy. If indoor collection is necessary, rooms must have at least 20 ACH ventilation.
When is a biosafety cabinet required in the laboratory?
A biosafety cabinet is required if specimens are centrifuged or cut/ground, regardless of the air change rate in the laboratory. For preparing sputum smears and loading Xpert cartridges, a ventilated workstation is needed only if ventilation is below 12 ACH.
Can germicidal ultraviolet lamps replace proper ventilation?
No. Germicidal ultraviolet (GUV) lamps should be used as a supplement to ventilation, not a replacement. They are recommended when ventilation does not reach the required 12 or 20 ACH in high-risk facilities and congregate settings such as detention centres.
Related on GMJ
Interconnected resources
Dictionary of Public Health
Conditions A–Z
GMJ News coverage
Quality & accreditation
- ASF Hospital — Standard 5 — Safety & Emergency Preparedness
- ASF Medical Transport — Standard 5 — Infection Prevention & Control
- ASF Laboratory — Standard 7 — Examination: Process & Safety
- ASF Laboratory — Standard 1 — Governance & Document Control
- ASF Laboratory — Standard 6 — Pre-Examination: Specimen Pathway
- ASF Laboratory — Standard 8 — Post-Examination: Reporting & Critical Values
Same guideline
- Administrative measures in health facilities — MSF TuberculosisChapter 14: Infection prevention and control
- Tuberculosis infection prevention and control (Chapter 14.1: Introduction) — MSF TuberculosisChapter 14: Infection prevention and control
- Therapeutic patient education and patient support services — MSF TuberculosisChapter 13: Adherence to tuberculosis treatment
- Factors that influence adherence — MSF TuberculosisChapter 13: Adherence to tuberculosis treatment
- Treatment delivery model — MSF TuberculosisChapter 13: Adherence to tuberculosis treatment
- Immune Reconstitution Inflammatory Syndrome in TB-HIV Co-infection — MSF TuberculosisChapter 12: Tuberculosis and HIV co-infection
Other guidelines on this topic
- Administrative measures in health facilities — MSF Tuberculosis
- Tuberculosis infection prevention and control (Chapter 14.1: Introduction) — MSF Tuberculosis
- Therapeutic patient education and patient support services — MSF Tuberculosis
- Factors that influence adherence — MSF Tuberculosis
- Treatment delivery model — MSF Tuberculosis
- Issuer
- Médecins Sans Frontières
- Guideline
- Tuberculosis
- Chapter
- Chapter 14: Infection prevention and control
- Type
- Clinical guideline (chapter)
- Edition
- Current online edition, 2026
- Status
- Current
- Published
- 2026-10-14
- Scope
- Environmental measures for tuberculosis infection prevention and control in health facilities
- Audience
- Health facility managers, TB programme staff, infection prevention and control teams, clinicians
- Evidence
- Expert consensus based on WHO policy
- Record history
- Created 23 Oct 2026 · updated 23 Oct 2026 · next check Apr 2027
Médecins Sans Frontières. 14.3 Environmental measures in health facilities. In: Tuberculosis [guideline]. MSF; 2026 Oct 14.GMJ Guidelines Library records are original summaries written by the GMJ editorial team from the issuer’s published document and reviewed by a physician. They do not replace the full guideline. The document is the copyright of its issuer and is linked, not hosted. Spotted an error or a newer edition? Tell the Guidelines Desk.
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