Temperature:  The high concentration of employees and the high level of occupation also increases the risk of uncomfortably high temperatures.  In addition, the computers which can be in use '24/7' also generate heat.  If the temperature is dropped in unoccupied areas of call centres to save energy, the occupied areas are at risk of becoming too cold.  This may be of particular concern on night shifts when a slightly warmer environment is likely to be required to compensate for the natural fall in body temperature.  These factors must be properly controlled so an acceptable temperature is maintained. 

Legal Requirements: Regulation 7 of WPR requires that 'During working hours, the temperature in all workplaces inside buildings shall be reasonable.' A reasonable temperature for a call centre will be around 19^oC.  It is not just air temperature that must be considered to achieve this level of thermal comfort: Relative humidity, air movement, number of people in the workplace, equipment and solar gain also need to be considered to ensure comfortable thermal conditions.  Air temperature should be measured with an ordinary dry bulb thermometer, close to workstations, at working height and away from windows, taking into account any localised effects of sunlight and radiant heat from office machinery.  A sufficient number of thermometers should be distributed throughout the work area to allow employees to monitor the temperature.  The provision of fans or heaters can help alleviate localised problems.

User Comments: The majority of the comments were about the variability in temperature: Too cold in the morning then too hot in the afternoon; too hot during the day but too cold at night; too cold in some parts of the building but too hot in others.  Although some offices were reported as airless, call handlers did not want ventilation to be draughty either. 

Relative Humidity:  The risk of low relative humidity is high in call centres.  The greatest risk is from the large number of computers, which, as already stated, can be generating heat 24 hours a day, seven days a week, and this can dry the air to unacceptable levels.  Low relative humidity can lead to dehydration which, in turn, can contribute to sore eyes, voice loss and headaches.  Skin rashes may also appear.  Unlike other physical stressors such as noise or temperature, people do not generally appreciate the impact of relative humidity on physical health and comfort so tend not to ascribe problems that they are experiencing to relative humidity levels. 

Guidance: Relative humidity for an office should be between 40% and 70% with the lower end being the most comfortable in warmer offices.  Employees should be provided with information on the risks of low relative humidity and their potential effects on physical and mental well-being and how to reduce these risks.

User Comments: A small number of comments were passed about humidity and how dry the atmosphere was in the call centre.  

Good practice

• Tea and coffee are diuretics so can exacerbate dehydration. Encourage call handlers to drink plenty of water or caffeine-free soft drinks instead.
• Position a sufficient number of cold water fountains throughout the call centre so water is available near workstations.  (HSE)