SMS, SBPP, and Tissue/Poly/Tissue: A Buyer's Guide to Nonwoven Fabrics in Medical Apparel

Disposable medical apparel listings are full of fabric acronyms: SMS, SBPP, spunbond, meltblown, tissue/poly/tissue. Buyers deserve to know what these terms actually describe, because the fabric determines how a garment feels, how it handles fluids, and what it costs. Here is the plain-English version.

What "nonwoven" means

Traditional textiles are woven or knitted from spun yarns. Nonwoven fabrics skip the yarn stage entirely: fibers, most commonly polypropylene in medical apparel, are laid into a web and bonded together through heat, pressure, or other processes. The result is a fabric-like material that can be engineered for specific properties and produced economically enough for single-use products.

Spunbond (SB / SBPP)

Spunbond polypropylene, often abbreviated SBPP, is made by extruding continuous polypropylene filaments and bonding them into a sheet. Its defining characteristics:

  • Relatively strong for its weight, with good tear resistance
  • Breathable, with an open structure that allows air movement
  • Naturally water-repellent, since polypropylene does not absorb moisture the way cellulose fibers do
  • Soft enough for garments worn directly against skin

Spunbond on its own is common in garments where comfort, coverage, and light fluid resistance matter more than barrier performance, such as exam capes and patient apparel.

Meltblown (M)

Meltblown polypropylene is produced by blowing molten polymer through fine nozzles with high-velocity air, creating extremely fine fibers. The resulting web has much smaller pore sizes than spunbond. On its own, meltblown is relatively weak, but its fine structure is what gives layered fabrics their resistance to liquid penetration.

SMS: the layered composite

SMS stands for spunbond-meltblown-spunbond: a three-layer laminate with meltblown sandwiched between two spunbond layers. Each layer contributes something:

  • The outer spunbond layers provide strength, abrasion resistance, and a comfortable hand feel
  • The inner meltblown layer provides the fine-pored structure that resists liquid strike-through

The combination is why SMS is one of the most widely used constructions in single-use medical apparel, including isolation gowns: it balances comfort, durability, and fluid resistance at a workable cost. Fabric weight, usually expressed in grams per square meter (gsm), also matters; heavier SMS generally means more substance and durability.

Tissue/Poly/Tissue (T/P/T)

Tissue/poly/tissue is a different construction family: a thin polyethylene film laminated between two layers of cellulose tissue. The tissue layers feel paper-like and absorb surface moisture, while the poly film in the middle stops liquids from passing through. T/P/T is common in exam capes, drapes, and gowns from many manufacturers. Compared with SMS, it is typically less cloth-like and less drapeable, and the tissue faces can tear more easily when wet, but it is economical and functional for short exams.

How fluid resistance is actually measured

Marketing language like "fluid resistant" has standardized test methods behind it. Two of the most commonly referenced in protective apparel are published by AATCC, a textile standards organization:

  • AATCC TM42 (Water Resistance: Impact Penetration) measures how much water penetrates a fabric when sprayed against it
  • AATCC TM127 (Water Resistance: Hydrostatic Pressure) measures the water pressure a fabric withstands before liquid passes through

When a supplier references these test methods, it is describing measured fabric behavior rather than a general impression. Buyers comparing products can ask suppliers which test methods apply to a given fabric and at what values.

What this means when you're comparing products

  1. Match the fabric to the task. Short, dry exams have different fabric needs than procedures with fluid exposure.
  2. Ask about construction and weight, not just the acronym. Two SMS gowns at different gsm are different products.
  3. Consider the patient experience. Softness, breathability, and drape affect how patients feel in the garment, which matters for longer appointments.

Our disposable exam gowns are cut and sewn in the USA from SMS and SBPP nonwovens, with fabric details listed on each product page.

Sources

  • AATCC. TM42: Water Resistance: Impact Penetration Test and TM127: Water Resistance: Hydrostatic Pressure Test. American Association of Textile Chemists and Colorists. https://www.aatcc.org

This article is provided for general informational purposes only. Fabric descriptions are general characteristics of material types, not performance claims about any specific product. Facilities should evaluate products against their own protocols and requirements.

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