PExTex Program Studies Spacesuit Cleanliness

As part of a larger ESA effort called PExTex, assessing suitable textiles for future spacesuit design, the Austrian Space Forum is leading a project called BACTeRMA, looking into ways to prevent microbial growth in suit inner linings.

"(S)pacesuits will most probably be shared between different astronauts, and stored for long periods between use, potentially in favorable conditions for microorganisms."

Malgorzata Holynska, ESA

When astronauts return to the Moon they will be bringing along a new generation of spacesuits, designed to withstand the harsh conditions of the lunar surface. But in keeping their human occupants safe and comfortable, these suits might also become a fertile environment for harmful microbial life – especially as astronauts will potentially be sharing suits with one another.

As a PExTex partner, the Austrian Space Forum (Österreichisches Weltraum Forum/OeWF), has focused on keeping the insides of spacesuits safe and healthy, through its ‘Biocidal Advanced Coating Technology for Reducing Microbial Activity’, or BACTeRMA for short.

“Think about keeping your underwear clean; it’s an easy enough job on a daily basis, thanks to detergent, washing machines and dryers,” explains ESA materials and processes engineer Malgorzata Holynska. “But in habitats on the Moon or beyond, washing spacesuit interiors on a consistent basis may well not be practical.

“In addition, spacesuits will most probably be shared between different astronauts, and stored for long periods between use, potentially in favorable conditions for microorganisms. Instead we needed to find alternative solutions to avoid microbial growth.”

PExTex Program Looking at Materials with Antibiotic Qualities

Traditional anti-microbial materials such as silver or copper might cause skin irritation in the close quarters of a spacesuit, and are likely to tarnish over time.

Instead the BACTeRMA team turned to so-called ‘secondary metabolites’ – which are chemical compounds produced by microbes to protect themselves against competitors or other environmental factors. Typically colorful in appearance, these compounds often have antibiotic qualities.

OeWF worked with BACTeRMA partner the Vienna Textile Lab, which possesses a unique ‘bacteriographic’ collection, to develop biocidal textile processing techniques, such as dying cloth with these bacterial metabolites. These materials were then exposed to radiation, moondust and simulated human perspiration to test their durability.

As a result, the BACTeRMA partners have gained valuable insights into the effectiveness and suitability of antimicrobial substances, such as violacein pigment and prodigiosin – known for its pinkish hue on dirty surfaces – on various textile materials.

The PExTex program is also studying new materials for the exterior of the suits to protect against radiation, dust an other issues faced by astronauts on the moon.

(Source: ESA news release. Images provided)