Office Chair Sponge Quality

The quality of sponge in office chairs is influenced by factors such as density, rebound rate, and compression set. When purchasing, it is necessary to comprehensively consider these indicators to select the appropriate product.

Density is a core indicator: The density of the sponge for the seat of a regular office chair should be no less than 25kg/m³. Government procurement standards require a seat density of ≥25kg/m³ and a density of ≥18kg/m³ for other parts. Mid-to-high-end products often use high-density sponge with a density above 45kg/m³. This type of sponge has moderate hardness, provides stable support, avoids large-area collapse, has full pores, good resilience, and superior durability. However, it should be noted that higher density is not always better: sponge with a density above 60kg/m³ feels too hard and can cause a sense of oppression after long-term use; while sponge with a low density has insufficient support and is prone to collapse after a few months. Considering support, comfort, and lifespan, high-rebound molded sponge with a density of 45-50kg/m³ is an ideal choice, especially for office workers who sit for more than 6 hours a day on average.

Rebound rate and compression set determine durability: The rebound rate reflects the sponge's ability to recover from deformation. High-quality products should have a rebound rate of ≥45%. The faster the rebound, the better the density and quality, providing continuous comfortable support. Compression set refers to the proportion of deformation that the sponge cannot recover from under long-term pressure. For a 75% compression set, it should be ≤5%, otherwise, it can easily lead to seat collapse. High-density molded sponge typically has a height loss rate of 4%-12% after 80,000 compression fatigue tests. If a zoned density process is used (such as high density in the center of the seat and low density at the edges), it can further disperse pressure and extend the service life to three to five years.

Purchase tips: You can initially judge the quality through a simple hand-feel test: press the seat cushion for 5-10 seconds and then withdraw your hand, observing the rebound speed. The faster the rebound, the better the quality. In addition, it is necessary to choose according to the usage scenario: if you need to sit for a long time, prioritize high-rebound sponge with a density of 45-50kg/m³; if the usage frequency is low, sponge with a density of 25-30kg/m³ can also meet basic needs. Avoid blindly pursuing high density and be wary of low-density products that are of inferior quality.