In terms of general ventilation for a manufacturing facility, successful work environments are ones one where employees are not feeling thermal discomfort and can be 100% productive throughout their shift. This type of environment is sometimes difficult to imagine in the summertime when the outside temperature is in the 90’s. However, a well designed ventilation system can provide a significant amount of Comfort Cooling to employees to keep them at or near their peak productivity.
Heat Loads
There are two types of heat loads that need to be addressed in order to provide Comfort Cooling:
- Solar Heat Gain
- Excess Ambient Heat
Both of these heat loads can be mitigated by a properly designed general ventilation system. To achieve this requires determining what type of fan should be used, how many are needed and where they should be placed to provide maximum benefit. I’ll go through a brief discussion of how to address each type of heat load.
Solar Heat Gain
This comes from the sun beating down on the outside of a building. It is the same effect as what happens when a car is parked in the hot sun. The hottest air from solar heat gain is found at the top of the building which is where exhaust fans should be located. To exhaust hot air, Eldridge uses wall mounted panel fans or roof mounted hooded ventilators and upblast fans. For most Comfort Cooling applications, the ventilation system should have enough fans to achieve 6 air changes per hour. With that level of air flow in and out of the building, the solar heat gain will be dissipated and the temperature inside will be the same as outside.
Excess Ambient Heat
We define this as the outside temperature when it exceeds 77ºF. Based on a Lawrence Berkeley National Laboratory study, human productivity decreases by 1% for every one degree that the temperature exceeds 77ºF. The type of fans used to mitigate ambient heat are spot cooling fans or HVLS (High Velocity Low Speed) fans. A word of caution here about these types of fans. They actually don’t change the air temperature. The Comfort Cooling effect provided is only perceived and is based on air movement across a person’s skin that evaporates sweat. Therefore, if the solar heat gain has not been dissipated first, these fans will be blowing hot air on employees which will make them feel hotter.
Because their cooling effect is only perceived when a person is directly in the airstream, spot cooling and HVLS fans need to be concentrated in places where the most people are present. HVLS fans can be used to cover a large area with air movement. Spot cooling fans are best used for creating air flow over a person standing in front of a piece of machinery.
Payback for Successful Work Environments
In addition to the satisfaction of having created a successful work environment for their employees, companies will actually see financial benefits from their investment in Comfort Cooling. When employees aren’t experiencing thermal discomfort, employee retention goes up and absenteeism goes down which reduces the costs associated with recruiting, training and overtime.
Workers are also more productive when they are cooler. As mentioned above, a study showed that productivity decreases by 1% for every one degree that the temperature inside the workplace exceeds 77ºF. Comfort Cooling can achieve a total temperature decrease (real and perceived) of 20 degrees which would translate to a 20% improvement in productivity. When all financial benefits of Comfort Cooling are added up, the payback period for the investment becomes very short.
Our Success is Your Successful Work Environment
At Eldridge, we are highly motivated and very passionate about using Comfort Cooling to create successful work environments. We know that Comfort Cooling is a win-win for employees to feel cool and for employers to see lower labor related costs. If you want to create a successful work environment for your facility, contact Eldridge today and we will have one of our ventilation specialist give you a free consultation on how we can achieve success together.