Between the dust, paint, welding equipment, and heavy machinery, construction workers are exposed to numerous toxins that could affect their health without the proper precautions. To keep employees, the public, and future building occupants safe, contractors use a myriad of techniques to reduce the risks of exposure to harmful substances and remain compliant with government and environmental policies. One such technique that construction drying services use is indirect-fired heat to warm work areas and create conditions that promote the successful drying and curing of coatings and building materials.
Indirect-Fired Heat Overview
An indirect-fired heater is like a gas- or oil-burning fireplace with a chimney. Its burn chamber contains the flame, which warms the heat exchanger. When air enters the chambers inside the unit, it gets warm as it passes around the heat exchanger.
The air that enters the heater does not make contact with an open flame, so the warm air produced is 100 percent clean, dry, and free of exhaust fumes and harmful gases. The heater vents combustion byproducts outside while heating the air inside, making it ideal for use in enclosed spaces that lack ventilation or air exchanges. Construction drying services may deliver the warm air produced by indirect-fired heaters to different locations on a site using ducts.
Reducing Exposure to Toxins with Indirect-Fired Heaters
Gas and Combustion Byproducts
When heating a space with devices that use fire, one of the greatest concerns is poisoning caused by noxious gases, such as carbon dioxide and carbon monoxide. Unlike direct-fired heating, in which air passes directly over an open flame before blowing into space, the flame in an indirect-fired heater remains inside the burn chamber. This means that exhaust and combustion byproducts, which could ignite or contaminate building materials, also remain within the heater’s components before they vent outside. Therefore, the warm air that the heater blows into the room is just that—warm air.
Indirect-fired heaters are ideal for construction drying as employees often work in enclosed spaces, particularly when the weather is cold or rainy. If a site used direct-fired heaters in an area without sufficient ventilation, the exhaust and combustion byproducts could cause workers to develop symptoms such as headaches, nausea, dizziness, breathing difficulties, and lethargy. Prolonged exposure can lead to brain damage and death.
Unlike direct-fired heaters, the warm air that indirect-fired heaters produce is clean and dry. This is an important consideration in regards to the health of the respective building, indoor air quality, and future occupants. Drywall, cement, surface coatings, flooring adhesives, fire retardants, and other building materials require a particular environment to dry and cure properly. Moisture in the air can prolong drying times and increase the risk of mold growth.
Indirect-fired heaters further promote material drying by creating and maintaining conditions that do not allow surfaces to achieve dew point temperatures, which may also promote mold growth. When surfaces cool and achieve a certain temperature, dew may form on them. Because the air that indirect-fired heaters blow is dry, it is less likely to increase relative humidity levels in a space. The warmth in the air prevents surface temperatures from lowering to dew point temperatures.
Whether the goal is to construct a green or LEED-certified building, promote the proper drying of materials, or ensure the safety of construction workers and the building’s health, indirect-fired heat makes sense. It offers similar benefits as direct-fired heat without the risk of dangerous fumes and mold growth. Polygon’s construction drying services include the use of high-volume indirect-fired heaters that use diesel fuel. This and other cost-effective temporary climate control solutions extend your working season, enhance productivity and keep your projects on track. Talk to a Polygon specialist today to learn more about the benefits of indirect-fired heat at your site.
[eflon via CC License 2.0]