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Do fans spread infection in clinical areas?

Three Part Question

In [clinical areas] does [the use of electric fans] lead to [increased infection rates in staff or patients]?

Clinical Scenario

It is midsummer''s day in a busy Emergency Department and it is sweltering outside. Your impervious, long-sleeved uniform (that the Trust insist you should wear for health and safety reasons) is moist with sweat. The temperature is 30 degrees centigrade and you are rushing around, like usual, trying to do three things at once.

You decide to turn the electric fan on but the nurse in charge tells you that Infection Control have removed all of the fans because they spread infection. The air conditioning has been out of use for a long time because it, too, apparently spreads infection.

You wonder whether there is actually any evidence that electric fans spread infection or whether it is more of a risk for the patients to be treated by an overheated, dehydrated, sweaty doctor.

Search Strategy

EMBASE 1980 to 2008 Week 30. Ovid MEDLINE(R) 1950 to July Week 4 2008. CINAHL 1982 to July Week 4 2008 using multifile searching

Google: [Search conducted 31/07/08]

The Cochrane Library Issue 2 2008.
[Fan/ OR] AND [exp Infection Control/ OR exp Bacteremia/ OR exp Septicemia/ OR exp Infection Prevention/ OR exp Airborne Infection/ OR exp Infection Rate/ OR exp Infection Risk/ OR exp Infection/ OR (infection OR bacter?emia OR septicaemia).mp.

Google: "infection, hospital, fan"; "workplace temperature regulations"

Cochrane:(fans):ti,ab,kw 64 records none relevant

Search Outcome

The search found: 84 papers in MEDLINE, 63 in EMBASE, 2 in CINAHL, 5 in CCRCT and 2 in CDSR and. One was relevant to the three-part question. No relevant papers were found using Google, although several items are discussed. The single paper is shown in the table:

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Trincado et al
United States
10 Non-infected pigs were placed in a building 10 m away from a fan-ventilated furnishing facility containing 150 5-month-old pigs who were infected with porcine reproductive and respiratory syndrome virus The two airspaces were connected via the fan, which was turned on 24 h per dayExperimentalInfection rates in the initially non-infected pigsNo pig developed an infectionPurely experimental. Not directly relevant to the three-part question, as Emergency Departments are usually (slightly) different to barns.


There is no published evidence that electric fans spread infection in clnical areas. There were no published data on the growth of concerning organisms on fans and their aerosolisation. There were no case reports of high infection rates associated with the use of worktop electric fans. The only relevant paper found that a fanning system could not be used to spread viral infection in a pig model. Surprisingly, regulations do not state a maximum workplace temperature. However, they do state that "during working hours, the temperature in all workplaces inside buildings shall be reasonable" (Health and Safety Executive). Current regulations also state that: "Where a reasonably comfortable temperature cannot be achieved throughout a workroom, local cooling should be provided. In extremely hot weather fans and increased ventilation may be used instead of local cooling". A Google search revealed that fans from Southend Hospital Foundation NHS Trust have been sent away for an ultrasound bath in deionised water then dried, tested and returned. No evidence was found for this practice but it is arguably a more pragmatic approach than simply banning electric fans.

Editor Comment

This BET will be updated when the full paper is available for review.

Clinical Bottom Line

There is no evidence that electric fans spread infection in clinical areas. Any future research to assess the safety of their use should incorporate cleaning programs.


  1. Southend University Hospital Foundation NHS Trust Early bath for Southend Hospital fans
  2. Health and Safety Executive What is the maximum/minimum temperature in the workplace?
  3. Trincado C; Dee S; Jacobson L; Otake S; Rossow K; Pijoan C Attempts to transmit porcine reproductive and respiratory syndrome virus by aerosols under controlled field conditions [Abstr] Veterinary Record 2004; 154(10): 294-297.