Spandex or elastane is usually a small but important part of a blend, providing stretch and recovery. High heat and chlorine can damage elastic fibers and reduce performance.
Because the companion fibers may have their own restrictions, follow the garment label and favor the most restrictive care requirement that applies to the finished item.
The fiber profile explains common risks. The sewn-in care instructions for your actual garment override any generic fiber-level guidance.
Care considerations
care label
Follow the finished garment's care label because spandex is usually blended with other fibers.
Blend care should follow the most restrictive relevant instruction.
Watch for: The companion fibers and garment construction can set stricter limits.
wash
Use warm rather than hot water when the label allows washing.
UGA Extension describes spandex as heat-sensitive.
Watch for: Excessive heat can damage elastic fibers.
bleach
Avoid chlorine bleach unless the product care instructions explicitly state it is safe.
Spandex is specifically listed as chlorine-sensitive.
Watch for: Chlorine can damage spandex and reduce elastic performance.
dry
Use low dryer heat only when tumble drying is permitted; otherwise follow the label's air-drying method.
Lower heat is the conservative approach for spandex-containing garments.
Watch for: High heat can damage elastic fibers and shorten garment life.