One of the most fundamental requirements of operating a cleanroom is, of course, the cleaning. That’s why when you’re developing or revising your contamination control strategy, you need to think carefully about your choice of cleaning detergent.


Annex 1 defines cleaning in its glossary quite simply as “a process for removing contamination e.g. product residues or disinfectant residues”. This means, to satisfy section 5.4 of Annex 1, the detergent you use should be validated to both remove residues or debris, and to minimise chemical, microbial and particulate contamination.  

Section 4.35 also specifies that, “disinfectants and detergents used in grade A and grade B areas should be sterile prior to use.” The guidance then notes that disinfectants used in grade C and D may also be required to be sterile where determined in the CCS.

In short, your cleaning agents have to be validated, and for many cleaning protocols, sterile.

Sterile neutral detergents and alkaline detergents are both commonly used in cleanroom environments because they are generally effective in cleaning without leaving residues or causing corrosion. 

There are other detergents out there–acidic and enzymatic among them. But, the ability of neutral and alkaline detergents to clean a wide range of surfaces while maintaining the required cleanliness standards makes them a popular choice for cleanroom cleaning protocols. 

However, these two detergents do have distinct properties and applications. So should you opt for a neutral or alkaline detergent? Understanding how they differ is helpful when it comes to choosing the most suitable option for your cleanroom environment. 

This blog will run through some of the advantages of each, to help you make an informed decision for your own cleaning protocol. 

Sterile neutral detergents: a gentle approach 

Sterile neutral detergents are formulated to clean delicate surfaces without causing damage or corrosion. 

Sterile neutral detergents offer the following advantages:

  1. Gentle cleaning action

 Sterile neutral detergents are mild and non-corrosive, making them ideal for cleaning sensitive materials such as glass, rubber, and certain metals. They remove surface contaminants without altering the properties of the cleaned surfaces.

  1. Broad compatibility

 These detergents are compatible with a wide range of materials commonly found in cleanrooms, including plastics, elastomers, and electronic components. This versatility makes sterile neutral detergents suitable for diverse cleaning applications.

  1. Reduced residue formation

 Sterile neutral detergents minimise the risk of forming residue after cleaning, ensuring that surfaces remain clean and free from unwanted deposits. This is particularly important in cleanrooms where even trace amounts of contaminants can compromise product quality.


Sterile alkaline detergents: robust cleaning 

In contrast, sterile alkaline detergents are engineered for more intensive cleaning tasks.

Sterile alkaline detergents offer the following benefits:

  1. Effective removal of stubborn contaminants

 Sterile alkaline detergents are highly effective at removing a wide range of contaminants, including oils, greases, proteins, and other organic residues. Their alkaline nature allows them to break down and emulsify stubborn soils, ensuring thorough cleaning of surfaces.

  1. Minimised particulate generation

 Cleanrooms require cleaning agents that minimise the generation of particles during the cleaning process. Sterile alkaline detergents are designed to reduce particle shedding, helping to maintain cleanliness levels and prevent cross-contamination.

  1. Enhanced microbial control

 The alkaline pH of these detergents provides additional microbial control, inhibiting the growth of bacteria and other microorganisms on cleaned surfaces.  

Choosing the right detergent for your cleanroom

The requirements of every cleanroom are different. Selecting the most suitable detergent for a cleanroom depends on a number of different factors. This includes the type of contaminants present, the materials being cleaned, and the necessary degree of cleanliness among other considerations. While sterile neutral detergents offer gentle cleaning for delicate surfaces, sterile alkaline detergents provide robust cleaning power for removing stubborn contaminants. In some cases, a combination of both sterile neutral and alkaline detergents may be necessary to best address different cleaning challenges in the cleanroom environment. 

By tailoring cleaning protocols to specific cleanroom requirements, operators can uphold the highest standards of cleanliness, ensuring product quality, regulatory compliance, and the safety of personnel. Read more in our product guide.