Barrier grades
45 gsm SMS: the surgical pack structure
45 gsm SMS balances barrier and breathability for surgical packs, drapes and lab coats. It is the structure most hospital tenders ask for.
At a glance
Specification at a glance
| Property | 45 gsm SMS typical range | Note |
|---|---|---|
| Structure | S15 / M15 / S15 | Balanced skins |
| Hydrostatic head | 80 to 120 mm | AATCC 127 |
| Air permeability | 40 to 80 l/m²/s | Breathable |
| Tensile MD | 38 to 48 N/5 cm | Drape ties and clamps |
| Tensile CD | 22 to 30 N/5 cm | Seam holding |
| Lint | Low | Suits surgical field |
Why surgical packs settle at this weight
A drape has to resist fluid strike-through during a procedure, hold clamps without tearing, and stay breathable enough not to create a heat trap. At 45 gsm the three requirements overlap. At 35 gsm the drape tears at the clamp; at 55 gsm the pack becomes stiff and hot.
Reinforcement where it matters
Most surgical drapes are not uniform: the critical zone is reinforced with a heavier SMS or a film laminate. The buyer specifies the base structure and the reinforcement separately, and the tender usually states both.
Sterilisation compatibility
Ethylene oxide is standard. Gamma and electron beam degrade polypropylene, so a dose study and often an antioxidant package are needed before the claim is made.
Other weights in this range
This grade sits in the SMS / SMMS range. Buyers comparing across weights usually ask for two or three of these at sample stage, because the decision is made on the converting line rather than on the data sheet.
- 35 gsm SMS - 35 gsm SMS is the lightest barrier structure we quote: a 15 gsm meltblown core.
- 55 gsm SMS - 55 gsm SMS is the heavy end of the breathable barrier range: higher hydrostati.
Compare this structure with your current fabric
Send the barrier requirement, the weight you run now and the monthly volume. We reply with the structure, the test values and a ship date.
Questions
Common questions
Does 45 gsm SMS meet EN 13795?
It can meet the standard performance levels for drapes and gowns when the finished product is tested. The fabric alone does not carry the claim.
Can it be sewn?
Sewing is possible but creates needle holes. Surgical products normally use ultrasonic welding or taped seams.
What colours are used?
Medical blue and green are standard because they reduce glare under theatre lights. White is used for non-theatre applications.