40-60% RH is the optimum condition for employee health and productivity in an office environment.
In many office environments there may be a requirement for humidity control throughout the year, due to air conditioning in the summer months, and heating in winter. Both will remove moisture from the air and prolonged exposure to a dry atmosphere will affect the health of staff, increase absenteeism and lower productivity.
Adverse effects of dry air include electrostatic shocks, which occur below a threshold of 40%RH. Other, less recognisable, effects include dry itchy skin, contact lenses prematurely drying out and causing discomfort, sore eyes and throat, and an increase in dehydration.
Considerable research and tests have shown that the transmission of airborne viruses, such as influenza, are greater at a low humidity, and optimum RH helps keep the body’s natural defence mechanism moist and reduces the amount of time particles remain airborne. Maintaining an optimum humidity therefore helps fight against infections in the office and reduces absenteeism.
The recommended level of humidity for human health is between 40-60%RH. To maintain this level large offices will employ industrial humidification systems within the central air conditioning system. However, in-room humidifier systems are available that can introduce moisture directly and discretely to a room’s atmosphere.