Meaning of NA and SA in the Polyester Staple Fiber (PSF) grading system

In industrial Polyester Staple Fiber (PSF), two grades that are frequently mentioned are NA Grade and SA Grade.

Because these grades are not based on international standards, but rather on market-based grading practices, their exact meanings are often difficult to understand clearly.

In this post, we will take a closer look at the differences between NA Grade and SA Grade in polyester staple fiber.

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What are NA and SA?

• SA Grade (Super A Grade)

  
  

  SA stands for Super A Grade and refers to a mid-level grade within recycled polyester fibers.

  
  

  It is mainly produced using finely crushed PET bottle flakes, where flakes from multiple bottles are mixed together, resulting in non-uniform coloration. As a result, the finished fiber typically shows a slight bluish tint, and in some cases may appear off-white.

  
  

  Because primary recycled materials such as PET flakes are used, the fiber exhibits high tensile strength and good elasticity.Despite being a recycled grade, SA Grade is relatively high-priced, and is therefore commonly used in applications that require better quality, such as furniture filling, bedding and quilt filling, and sleeping bag insulation.

• NA Grade (Normal A Grade)

  
  

  NA stands for Normal A Grade and refers to a lower grade within recycled polyester fibers.

  It is mainly produced by re-melting already manufactured polyester fibers, which results in reduced tensile strength in the final product. In terms of appearance, the fiber typically shows a grayish color.

  
  

  Within recycled grades, NA is considered a lower-quality grade and is therefore commonly used in applications such as geotextiles and automotive nonwoven materials, where appearance and high mechanical performance are less critical.

  
  

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Are NA and SA international standards?

The NA/SA grading system is not an official classification defined by international standards.It is a manufacturer-driven grading system mainly used by PSF producers in Korea, China, and other Asian countries to internally differentiate quality levels.

As a result, even within the same NA grade, tensile strength and elongation can vary depending on the manufacturer.

From a buyer’s perspective, the selection criteria can be summarized as follows::

Grade	Quality Characteristics	Typical Applications	Price
SA Grade	Relatively high uniformity, low level of contaminants	Bedding, furniture	Medium
NA Grade	Cost-oriented, noticeable variation in color and uniformity	Geotextiles, sound-absorbing materials, filling materials, large-scale industrial use	Low

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DK FIBER’s NA / SA Grading Criteria

DK FIBER also provides polyester staple fibers with subdivided SA and NA grades.

At DK FIBER, the SA grade is generally marketed as “Super A”, while the NA grade is typically sold as “Grade A.”

DK FIBER’s Super “A” grade fibers offer high strength and stiffness, and are supplied to multiple furniture manufacturers.

DK FIBER’s Grade “A” fibers, although classified as a lower grade, maintain reliable and consistent quality and are supplied on a monthly basis to a sleeping bag manufacturer in Canada.

Both products are GRS certified, and Transaction Certificates (TC) can be issued.For further details, please visit the DK FIBER official website.