Medical devices and pharmaceutical products are becoming complex to face up to the new requirements and needs of the sector.

The materials are evolving and leading to new emerging products with physical properties that are sensitive to high temperatures, including prostheses, syringes, gloves, saline bags and implants, as well as products with a material composition such as resin, rubber and plastic.

For this reason, these products (also named ‘thermo sensitive products’) cannot be sterilised using a traditional method such as for example steam sterilisation.

The sterilisation methods also had to evolve to face up to these new obligations and necessities, to guarantee a perfect sterilisation completing the integrity of products to sterilise. This has to give rise to new methods of low-temperature sterilisation such as radiation or ethylene oxide (ETO) sterilisation.

For more than 30 years, ETO sterilisation has been gaining popularity thanks to its efficiency and good results in the sterilisation area.

What is the ETO?

ETO is an odourless and colourless gas that sterilises and destroys microorganisms, penetrating and propagating into products to sterilise. Moreover, it can penetrate and propagate porous and difficult-to-reach materials without deteriorating.

This sterilisation process is efficient, thanks to its several advantages, including:

  • Propagation in all places, even the inaccessible areas of the product
  • Goes through the packaging containing the products (such as polyethylene films)
  • Depyrogenation of dead cells
  • Sterilisation at low temperatures (between 25ºC and 60ºC) guaranteeing the non-deformation and the non-destruction of the products.

ETO is one of the most effective processes for many products that cannot be sterilised by traditional methods, for example, cameras, syringes, gloves, saline bags, gums, some plastics and optical instruments.

Another important point to highlight regarding ETO is that it is an explosive, flammable, carcinogenic, mutagenic and toxic gas. The standards and international regulations are very strict with this process to ensure process sterilisation and employee safety.

Ethylene oxide sterilisation process 

The ETO sterilisation process comprises three phases:

  • Conditioning or preconditioning – This phase involves preparation of the products to allow an optimal gas penetration, using heat and humidity
  • Sterilisation – The products are sterilised thanks to an appropriated sterilisation cycle.
  • Ventilation or aeration – The goal is to eliminate all ETO residuals inside the products and packaging

To get an optimal sterilisation process, it is important to have an adequate relation with gas concentration, humidity, exposure time and temperature.

All of these parameters, together with other important parameters such as pressure, flow and level, should be considered in the design, manufacturing, programming, commissioning and validation of the ETO chambers to provide a safe, reliable and effective process.

A perfect control of the process and great know-how of this sterilisation method are essential for the sterilisation success.

ETO sterilisation process, ideal for a large number of products

Thanks to its perfect penetration on multiple layers of breathable packaging and excellent sterilisation without modification of the physical proprieties of products, this process is optimal for the following products:

  • Catheters
  • Syringes
  • Saline bags
  • Assembled complex devices
  • Products with packing
  • products with integrated-electronics
  • Multi-lumen tubing products
  • Stents

The advantages of this sterilisation method include:

  • High efficiency, destroying and eliminating virus, bactericide and fungicide
  • Ideal for sensitive materials to high temperatures, ensuring neither deformation nor destruction of the load
  • High diffusion coefficient in wrapping, creases, basically in any difficult access area
  • No alteration of physical properties of the sterilised product

ETO sterilisation solutions by RSD

In order to ensure an optimal process, it is important to entrust these projects to professionals who know and understand every step of the process, as well as the sector requirements.

RSD specialises in ETO sterilisation. Its experience and know-how allow it to offer full turnkey solutions focused on this process.

It is in charge of every phase, including designing, manufacturing, programming, validation and commissioning. The company delivers facilities adapted to the client’s requirements and needs.

Not the least, the fulfilling of applicable stringent international standards is part of RSD’s standards, as well as ATEX regulations and good manufacturing practice (GMP) normatives.

Safety for process and personal is a priority for RSD, and risk analysis is defined from the very beginning of the design, and is also applied during manufacturing and programming phases. The company’s ETO chambers are 100% automatised and include a control system developed by RSD.

RSD proposes highly efficient turnkey ETO sterilisation solutions with reliable, efficient and safe processes.