How to wash a reusable surgical face mask [guide]

How to wash a reusable surgical face mask [guide]

Washing guide for reusable medical mask made of recycled polyester

Keep surgical face masks TYPE II and TYPE IIR are made from PolyBiotech medical technical textile (recycled polyester) which has been developed over many years including special technology to make it biodegradable. So even though Keep surgical mask looks like fabric, it is NOT, it is using polyester fiber as basis for the medical textile making.

First wash at low temperature, and then iron

Keep surgical face masks need to be washed at low temperatures, 30 degrees (86 Fahrenheit) and MUST be followed by ironing with a hot iron, the highest possible (do not iron ear loops or ear loop adjustments, just the mask part).

And Yes, you read correctly.

  1. Wash at low temperature
  2. Iron the mask with a very hot iron

The Keep reusable surgical mask (polyester) MUST be washed at low temperature, followed by ironing with Very Hot iron and not what you read as recommended by some governmental sites, which is false.

Follow these instructions when washing your Keep reusable surgical face mask, to maintain the medical mask properties.

We are experts in medical mask textiles, and we provide washing and maintenance guidance based on laboratory tests and evidence and research done by experts, not on layman assumptions.

Why You Should Follow The Washing Instructions

Properties of cotton fabric versus polyester (PolyBiotech):

Bending properties, drape and density of fabric determines the adjustment of clothing to the human silhouette. For polyester, which Keep surgical mask is made of, bending properties remain same and are not impacted by washing if it is followed by ironing.

Bending length is related to the ability of a fabric to drape and bending rigidity is related more to the quality of stiffness felt when the fabric is touched and handled. Bending length increases as the number of laundering cycle’s increases up to five cycles, and gradually decreases thereafter. Starting from the considerations that the thickness of a cotton fabric decreases after 5th repeated cycles and in a greater degree when ironing/laundering fabric samples, so lower bending rigidity are remarked. No significant change of bending properties of a polyester fabric has been observed with ironing polyester fabric inter launderings compared to bending properties of fabric samples only laundered.

For non-medical textile, washing and ironing has a deteriorating effect.

Washing  and ironing destroys cotton fiber, which means the cotton fabric is stretched and it looses its shape.

Keep surgical face mask is made from polyester (PolyBiotech) which has a thermosetting and therefore repeated washing and ironing has minimal effect on the properties of the Keep washable face mask, see the low % in figure 4 versus the high in table 3.

Figure 3 (below) shows that the shrinkage of the cotton fabric increases obviously during the first five cycles and then achieved  a steady value after  10  laundering cycles.

Shrinkage in  polyester fabric increases slightly after 5 washes (figure 4). In fact, Polyester fabrics undergo a thermosetting cycle in industrial manufacturing to stabilize its dimensions.

Source: Effects Of Repeated Ironing-Laundering Cycles On Cotton, Cotton/Polyester, And Polyester Plain Fabrics (International Journal of Applied Research On Textile)

Lab tested for washing and ironing in accredited laboratory

Keep surgical face masks are lab tested for washing and ironing in accredited laboratory for doing washing and testing medical devices which Keep is regarded as according to the EU MDD 93/42 and MDR 2017/745 laws for medical devices including surgical masks.

Keep surgical mask has been washed and ironed in an accredited laboratory and the tests show the same result, that there is a minimal change in the BFE after washing+ironing the Keep surgical face mask 15 times at low temperature, and followed by ironing the mask, to reset the thermosetting.