Opening windows may not always be the best answer if there is no airflow or it is hotter outside. An obvious solution is to install air conditioning throughout the building or in rooms and offices which get particularly hot. This may of course not be practical in some cases, whether due to cost or other reasons. The next best alternative solution is to provide workers with fans and plenty of drinking water. Preventing direct sunlight by keeping blinds closed will also help reduce the temperature.
Another way of improving the feel of hot conditions is to optimise the humidity level of the air. This can be checked using a special thermometer that reads the humidity as well as temperature. The most comfortable humidity level to work in is between 40% – 70%. Too low can result in staff feeling dry and thirsty, while too high promotes a sweaty atmosphere. Using a de-humidifier in the office can help achieve the ideal humidity levels.
For employees that work outside, you could consider where possible adjusting their working schedules to cooler times of the day. While adjusted schedules are not always possible, perhaps due to restrictions set by planning laws or the impact on the surrounding community, you should provide somewhere cooler where outdoor workers can take breaks to escape the heat.