Cooling systems are a key safety tool
By Barb Zuehlke
Nothing feels better on a hot day than a gentle breeze. And as a safety tool in the form of a cooling system or fan, it can prevent heat stress and increase productivity.
Heat stress can cause a breakdown in the body's ability to keep itself cool which then requires medical attention and time off from work for recuperation. Another impact is the effect on workers' performance. Heat can reduce the ability to concentrate thus affecting comprehension, logical thinking, and productivity. Symptoms include headaches, fatigue, drowsiness, negative moods, and an increase in accidents.
OSHA recommends a variety of engineering controls including general ventilation, spot cooling, evaporative cooling, and cooling fans to reduce the hazards of heat exposure.
For most maintenance facilities, air conditioning isn't feasible. It's cost prohibitive and impractical as the area is usually open to the outside air. But airflow can be improved with stationary fans, evaporative coolers, and ceiling-mounted fans.
Stationary fans are the image that most often comes to mind when thinking of cooling systems. But in a large area, the number of fans required to make a difference in a maintenance facility can be costly.
Evaporative coolers provide cool air for the workplace using an evaporation process. Water is used to reduce the temperature of air coming into the unit. A high-powered blower then disperses the cooled air. Benefits include the lowering of the actual air temperature, lowering the effective temperature (what you feel), and reducing radiated heat. Some models are portable so they can be used where most needed (spot cooling).
Maintenance requirements include emptying and replacing the water reservoir once a week to prevent scale or mineral deposits from building up, and cleaning the water system and filters at least once during the season or more depending on usage.
Campbells Port-a-Cool, Schaefer Ventilation Equipment, and Patterson are among the companies that provide this type of cooling system. The Ice Cube from Patterson offers 1,500-square-foot coverage. Port-a-Cool units feature cooling capacity from 600 to 3,500 square feet depending on the model.
Ceiling fans are an economical choice for air movement. Besides the operational effectiveness, they are inexpensive to operate.
The high-volume, low-speed (HVLS) ceiling fan uses aerodynamically designed blades to create as much airflow as possible to as many workers as possible. This type of fan moves a lot of air by moving a very large column of air very slowly. The effect is a gentle breeze which improves the body's ability to cool itself through evaporation of perspiration without affecting work processes. HVLS fans can reduce heating, cooling, and ventilation costs.
The high-volume, low-speed fan technology was developed by Walter Boyd, co-owner of MacroAir Technologies, to create a system to cool dairy cattle; another industry whose productivity and efficiency is affected by heat. The fans feature 10 airfoil blades that incorporate designs developed at NASA. The blades are manufactured using the latest aluminum extrusion technology to produce the large and lightweight hollow foil shape. The blade's weight and balance enable it to be powered by a 1-hp or lower motor. The large blades move a large amount of air but at a lower rpm than high-speed fans, thus requiring less maintenance and extending service life.
Another benefit of HVLS fans is de-stratifying the uneven temperatures that occur from floor to ceiling. Stratification is the temperature differential of approximately 1 degree per vertical foot. The fans can move up to 140,000 cfm of air and cover up to 20,000 square feet thus evening out uneven temperatures. HVLS fans can also be used in conjunction with evaporative coolers or high-pressure misting systems. And they also act as a bird and bug repellent. Once a fan is installed, bugs and birds seem to disappear, creating a more pleasant working environment. MacroAir Technologies and Big Ass Fans (formerly HVLS Fan Co.) offer HVLS fans.
Schaefer Ventilation offers circulating, exhausting, evaporative cooling, and infrared heating.
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