Selecting Cold Sterilants for Your Decontamination Process

By Sandra Hulme

As tragic events like the NECC meningitis outbreak have shown, maintaining a sterile cleanroom is a complex process that requires continual evaluation. It must keep up with the challenges of keeping out a complicated external environment, be resilient to evolving microbial threats, meet strict environmental standards and still offer a safe place in which humans can work.

It’s not enough to follow a decontamination process as a matter of course, simply because it’s what you’ve always done. This is an area that is as open to new legislation and standards as it is to new threats of contamination.

The good news is that it is also an area of innovation with new anti-microbial technologies being researched and developed all the time.

The importance of using appropriate decontaminants in your cleanroom

Selecting a sterilant for your cleanroom is not as straight-forward as matching the most obvious decontaminant to the biohazard you want to mitigate. There will usually be other issues to consider such as cost, equipment requiring sterilization and how quickly decontamination must occur.

Then there is legislation and how changing laws and standards are impacting sterilisation processes, working conditions and the overarching business model.

With the recent proposed reclassification of formaldehyde as a biocide, for example, organisations have been forced to re-think how they should protect their cleanrooms against the toughest bio-contaminants. If the reclassification goes ahead, they must also seek a solution that can compete with formaldehyde on cost.

There is good reason for this reclassification, however, as formaldehyde has been proven to be a Class 1B carcinogen and a Class 2 mutagen. Decreasing the significant burden to employers and the wider economy, of occupational injuries and diseases, including those caused by exposure to carcinogens such as formaldehyde, has influenced the new International Standards Organisation’s first set of standards for occupational health and safety systems, ISO 45001 due out early next year.

Employees must be protected equally from potential exposure to disease as they are from harmful chemicals. Yet a sterile cleanroom is also absolutely essential and cold sterilants are offering the most versatile options today, to suit almost any cleanroom.

How to select the right decontamination system and cold sterilant

The most versatile solutions are dry fogging systems. They produce vapour that can reach all areas of a cleanroom, distributing sterilants comprehensively and quickly.

Dry fogging is even safe in areas containing heat-sensitive equipment, surfaces or other substances, making it suitable for a wide range of applications. There are also wet fogging options available. The chemicals you need to use may dictate the option that’s best for you.

If you work in the food industry, for instance, hydrogen peroxide and peracetic acid have both been used safely in these environments, and for medical applications, for over 30 years.

Your choice of cold sterilant will also be determined by the decontamination unit you’re using and any other equipment that might be affected.

The supplier of your cleanroom bio-decontamination system should be able to provide you with a compatible cold sterilant, but if you’re looking to change suppliers, answering this question should be a priority.

When looking for a cold sterilant, ask the following questions:

  • What chemicals are present in the sterilant?
  • How effective is the solution? Can you see some evidence?
  • Has the cold sterilant been validated according to pharma standards?
  • How safe is the sterilant for our users and our surfaces?
  • Is the solution safe for the environment? Is it bio-degradable?
  • What limitation is there on transport and storage of the cold sterilant?

 Cherwell’s Recommended Cold Sterilants

Actril and MinnCare are our cold sterilants of choice. Both of these are versatile solutions that meet a broad range of criteria and have been validated according to pharma standards, are safe for the environment and are extremely effective solutions.

1. Actril Cold Sterilant

Actril Cold Sterilant is a well-known decontaminant and as a ready-to-use and fast acting solution, has been used by pharmaceutical companies around the world for the past ten years. Actril works by disrupting Sulfhydryl and Sulfur bonds in proteins and enzymes and breaking down important components in cells through oxidative disruption.

It’s effective and ideal for decontaminating hard, non-porous surfaces including counters, walls and floors. It’s a broad spectrum sporicide that is safe for both its user and the environment, and is not subject to any restrictions for transport and storage. A fast-acting chemical, it gets to work in just a few minutes. This cold sterilant can be used as a spray, without the need of a dispensing system.

Find out more about Actril Cold Sterilant here.

3. Minncare Cold Sterilant

Minncare Cold Sterilant is a peracetic acid solution suitable for surface decontaminant of hard, non-porous surfaces such as glass, stainless steel or plastic. It works by stopping organism growth through oxidisation of microbial cell proteins and enzyme systems. It also effectively removes biofilms.

Developed by Minntech for use on reverse osmosis (RO) membranes and their associated distribution systems, Minncare is widely used on thin film composite and cellulose acetate membranes.

With superior biocidal activity, Minncare is also biodegradable and will decompose into oxygen, water and acetic acid. It also produces no toxic aldehyde vapours for your employees to breathe.

Find out more about Minncare Cold Sterilant here.

Selecting the right cold sterilant for your decontamination unit and process will do more than keep your cleanroom sterile and safe. It will also ensure you’re compliant with the latest health, safety and environmental standards and present a good business case.

If you’d like to know more about cold sterilants, decontamination units or for some tips on maintaining a sterile cleanroom, download our Pocket Guide to Cleanroom Decontamination.

Download Cherwell's Guide to Cleanroom Decontamination


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