How Harness Materials are Made

Prior to the 1960s, cotton was the fabric of choice for all industrial products that needed textiles.  Although the fabric was cheap and plentiful, it did not hold up well in harsh environments. By the early 1960s, synthetic blends became available for American manufacturers. Once people experienced the rugged durability of synthetic fabrics, it was clear that those materials should be widely available for industrial companies that needed to have more robust textiles in their products. With the new demand for synthetic materials, textile manufacturing established a fabrication process for making synthetic textile materials. For our purposes, we will be focusing on the steps used in a web strap textile manufacturing facility.

The first phase of production begins with synthetic textiles in a raw material stage. Raw nylon or polyester material will arrive in spools that are about the size of a roll of toilet paper. Then, hundreds of ends of those raw materials are fed through holes in a beam that is connected to another set of spools. Those spools are sent to a machine called a twister. 

The twister turns the raw spools of thin material into slightly thicker strands of material and places them on bobbins. Those bobbins are placed on another beam before going to the warping section of production. Warping involves taking the bobbins of material and preparing and positioning them for the loom where the weaving process occurs.

The weaving looms determine the thickness and other physical characteristics of the web straps. This step is where a specific weave pattern will be developed. Weave density and tightness will be created by the loom. Almost every loom in modern American factories operates under an automated system, but, it should be noted that people used to do this weaving by hand during the early years of manufacturing. This step is exciting because it is the time in the production process where raw materials offer the first glimmer of a recognizable finished product. Once a web strap has been woven, it is moved to the dyeing section of the manufacturing process.

During dyeing, there are two different processes that are used depending upon the type of material that is being dyed. If polyester is being dyed, it goes through the Thermasol process which is followed by dry heat and rinsing in wash tanks. If nylon is being dyed, it goes through a piece-dyeing process, which is followed by steaming and rinsing in wash tanks. Each heating process allows the dye to set in the fabric. Then, the rinses allow any excess dye to be washed out of the harnesses to prevent the dye from bleeding during field use. Once the dyes have been set and rinsed, the harness is ready to have lengths cut for testing purposes.

(Visit last week’s blog to learn more about textile tensile testing!)

Once the textiles have been tested to meet different fall protection standards, they go through a finishing process. Finishing typically involves spraying the textiles with chemicals to make them more flame retardant, abrasion resistant, static resistant, or stain resistant. Some textile manufacturers want specific treatments for their textiles and this would be the phase of production where the textiles would undergo a specific treatment rinse. For example, if a fall protection manufacturer wants to make a harness for an oil rigger, they are going to request that they get a textile that has been treated for stain and abrasion resistance. Meanwhile, another textile that is more flame retardant will be used to make a fall protection harness that is designed for people who are welding at height.

The final step in the production of synthetic textiles is blocking.  Blocking is an industry term for preparing the textiles for transport to other manufacturing companies. However, there are several different ways that the textiles can be packaged. Webbing textiles can be placed on rolls, spools, or cut into long sections and placed in a box. Depending upon how the fall protection manufacturer likes to work with the materials, the textile manufacturer will package the textiles in whatever way works most efficiently for their customers.

Once the final product has been blocked in accordance with the customer’s wishes, the textiles are shipped to another manufacturer. Once they arrive, the textiles will go through a sewing process where the textiles (in this case, synthetic web straps) will be turned into the finished product. In the case of fall protection products, the web straps will be turned into either a full body harness or a web strap lifeline. Once the harnesses or lanyards have been constructed, those products will be shipped to the companies that sell the fall protection systems to industrial and construction facilities. And after a facility has installed a fall protection system and undergone training to use the system, workers will wear the harnesses as they carry out various tasks at elevation.