Cleaning can be defined as the removal of residues from previous batch, other residues, and traces of cleaning agents. There are several mechanisms associated with cleaning of equipment.

The mechanisms involved can be mechanical action, chemical action between the residues and the cleaning agent. The selection of cleaning agent and mechanism involved in cleaning is largely dependant on the process residue to be cleaned.

Cleaning Mechanisms

The cleaning mechanism totally depends on the selection of cleaning agent and type of residue to be cleaned. The four main types of cleaning mechanisms are:

  • Dissolution
  • Saponification
  • Wetting
  • Emulsifying

Many cleaning compound agents perform several functions at once. Butyl, for instance, can serve as a wetting or surface tension reducing agent as well as a solubilizing agent. It also can contribute to emulsifying capabilities when combined with anionic surfactants or soaps (alkali-metal salts of carboxylic acids).

Many cleaning compound agents perform several functions at once. Butyl, for instance, can serve as a wetting or surface tension reducing agent as well as a solubilizing agent. It also can contribute to emulsifying capabilities when combined with anionic surfactants or soaps (alkali-metal salts of carboxylic acids).


Dissolution is the process by which a solid or liquid forms a homogeneous mixture with a solvent or solution. This can be explained as a breakdown of the crystals into individual ions, atoms or molecules and their transport into the solvent.

The mechanism involved in this type of cleaning is solubility of the residue in the cleaning agent or solvent. The monobasic buffers i.e. sodium chloride are soluble in cool and hot WFI. Ethylene glycol butyl ether is soluble in water as well as oil is also used in solubilizing agent. Chelating agents and builders are added to the formula to keep water hardness from interfering with the cleaning process.

Rate of dissolution is depend on:

  • Nature of solvent or residue to be dissolved
  • Temperature of solvent
  • Presence of mixing
  • Area of contact
  • Presence of inhibitors


Saponification can be defined as “hydration reaction where free hydroxide breaks the ester bonds between the fatty acids and glycerol of a tri-glyceride, resulting in free fatty acids and glycerol”, which are each soluble in aqueous solutions. This process specifically involves the chemical degradation of lipids, which are not freely soluble in aqueous solutions. Heat treated lipid residues are difficult to remove than non-heat residues due to polymerization.

Saphonification plays a critical role in cleaning lipids which are present in the areas of process involving cell growth and cell processing i.e. Bacterial fermentation, Cell disruption process


Wetting can be defined as a process “involves the lowering of the surface tension of the cleaning solution, thus allowing it to better penetrate residues that are adhered to equipment and piping surfaces”. Wetting agents, or surfactants, are often used in relatively small amounts and they can substantially reduce the quantities of cleaning agent (in this case, alkali) required for residue removal.

Advantages of Wetting include:

  • Lowers the surface tension of the cleaning solution
  • Allow better penetrate residues which are adhered to equipment
  • Used in small amount
  • Sticky residues which are hydrophobic in nature get easily removed

Water acts as a solvent that breaks up soil particles after the surfactants reduce the surface tension and allow the water to penetrate soil (water is commonly referred to as “the universal solvent”).


Emulsifying and suspending agents are often used to keep residues from precipitating by providing “hydrophobic groups” onto which hydrophobic areas of residues can associate, thus preventing them from associating with other residues and forming larger particles which are likely to leave solution. These agents also typically have “hydrophilic groups” which keep them very soluble in aqueous solutions of moderate to high ionic concentrations.

Emulsifiers increase the capacity of a cleaner to emulsify non-soluble compounds in the cleaner. i.e. anionic soap surfactants, cationic surfactants, neutral surfactants

Advantages of Emulsifying agents include:

  • Prevent association of residues
  • Allow the residue to precipitate and not allow thdse residue to redeposit on surface


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‘To the Cloud or not to the Cloud, that is the question.’

While it’s certainly a familiar question, with apologies to Hamlet, there is a question that tends to come first: “What is the Cloud in the first place?” Have you seen this on-line graphic lately of a young child who is just looking at you with the caption – ‘There is no cloud…’

Information Workers

The reality for most ‘information workers’ is that as long as your keyboard, mouse and monitor have something to plug into and data displays, all you really need to see is where that ‘something’ plugs into the wall so you can be sure you have a physical connection.

What’s on the other side of the wall – or even if there is strictly speaking no ‘other side’ – is not the users concern. You don’t need to have physical computing resources right next to you as long as the ‘virtual machine’ you are working on is properly provisioned and the latency (or ‘lag/response time’) isn’t large enough to be an issue.


The physical computing resources matter if you are doing a lab analysis with physical samples on instruments or using an automated line to produce product. In the land of data analysis, reporting and document production, the data needs to be available, not present.

From the enterprise perspective however, what is ‘present’ behind the wall is a true concern. Since compliance to regulations means ‘control,’ how the cloud supplies and protects those resources and the information they provide needs to be documented under a defined quality management system. While cloud vendors are glad to quote services and prices, they have not always been forthcoming about how things are done in their building.


The move to the cloud is a physical move – of your data, applications and possibly compute and platforms – to somewhere else. The somewhere is physical while your usage and controls become logical and virtual. If that makes you feel uneasy – or if you prefer ‘risk averse’ – you are not alone.

Outsourcing is a concept that brings joy to financial / accounting types, but for those involved with compliance, quality and validation, it brings a new set of challenges and concerns. It should recall the words of Mr. Murphy – “Nothing is as easy as it looks, everything takes longer than you expect AND if anything can go wrong, it will – usually at the worst possible time.”

Current warning letters addressing data integrity have focused on site forensics – data in trash cans, bags of shredded records. When it comes to the cloud, there is no ‘there’ for you to access – unless there are the careful negotiations, detailed SLAs and rigorous audit/ follow-up required to give your enterprise the confidence it needs to move forward.

Do your current internal resources have the expertise and the flexibility to deal with a vendor you have to trust significantly? This is more complex than a contract manufacturer where you can review the SOPs for compliance, watch the process and then have the product independently tested.

GxP Compliance

The draw of the cloud is that everything is ‘out there’ – available ‘just by an e-mail’ – and not running up costs on your premises. What will happen if suddenly it isn’t ‘there?’ Whose fault will it be – oh, must be the vendor. Good idea – blame the vendor – but there’s many a wire between your ‘here ‘ and their ‘there.’

Will it be your communication vendor, some nameless third party supplier or cloud hardware, software or internal network failure? There are many ABCs in the cloud – SaaS, IaaS, PaaS, Haas, AaaS, ITaaS – and the list goes on. It is critical to have the proper support to be able to straighten all those letters out to spell ‘GxP compliance.’

Cloud Provider

Everyone wants their cloud provider to look like the image below. But that will take attention to detail, technical understanding and the ability to ask ‘the next questions’ needed to assure quality and compliance.

Those will include security at multiple levels and how are they going to maintain those perfect cables when the one in the middle breaks?

There are many items to be considered – here are some more:

  • What application(s) and data are going to be ‘sent to the cloud?’
  • What in-house processes / systems need to access that data?
  • Where will the data physically be held and what are the laws in that location if outside of the USA?
  • What are the backup provisions for the cloud providers’ servers and storage?
  • What is the security plan – including physical, logical and access controls?
  • How will your audit resources be granted access and under what ground rules?
  • Does the vendor provide a Quality Manual or Quality Management System document for review?
  • Does their contract include a ‘non-cookie cutter’ Service Level Agreement (SLA) that details your focus points?

About Azzur IT


Azzur IT is an Azzur Group Company providing a broad range of services, including IT Quality & Compliance auditing services; computer system validation (CSV); application selection, implementation, integration and project management services; IT infrastructure, operations & data center assessment; risk-based data integrity assessment; compliance remediation projects; SOX consulting; process improvement and change management.



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Changes to equipment and documentation is an integral part of the whole GMP process in any regulated facility. In this article we will discuss how equipment is designed in a GMP facility and how good documentation practices are an essential part of quality assurance and GMP.

The content of this article has been taken from module 7 of our eLearning module on Good Manufacturing Practices (cGMP) within the life sciences.

You can view this module in full by viewing the video below.

cGMP eLearning Module – Compelling, Engaging and Interactive



All equipment is designed, constructed and located to suit their intended use and to facilitate easy maintenance and cleaning.

Equipment is installed in such a way as to prevent any risk of error or of contamination, and cleaned according to detailed and written procedures and stored only in a clean and dry condition.

Production equipment should be designed in such a way as not to present any hazard to the products.

The parts of the production equipment that come into contact with the product must not be reactive, additive or absorptive to such an extent that it will affect the quality of the product and thus present any hazard.

Any defective equipment should, if possible, be removed from production and quality control areas, or at least be clearly labelled as defective. When not in use, equipment should be covered to ensure it remains clean.


Balances and measuring equipment of an appropriate range and precision should be available for production and quality control operations.

All measuring devices are required to be calibrated and checked at defined intervals by appropriate methods, and adequate records of such tests should be maintained.


Fixed piping should be clearly labelled to indicate the contents and where applicable, the direction of flow.

Water pipes used in production (e.g. Purified Water, Water for Injection) are sanitised according to written procedures that detail the action limits for microbiological contamination and the measures to be taken.

Electrical circuits should be identified, and a record maintained of the load on each circuit to prevent inadvertent overload.


Good Documentation Practices are an essential part of quality assurance and GMP.

It is important for a manufacturer to get the documentation right in order to get the product right.

GMP Documentation e.g. Site Master File, Specifications, Batch Manufacturing Formulae, Batch Manufacturing Records, Processing, Labelling, Packaging, Testing Instructions, Standard Operating Procedures, Protocols, Technical Agreements, Records, Certificates of Analysis, Reports etc. should contain the following attributes of a good document:

They should be:

  • Attributable
  • Legible
  • Contemporaneous
  • Original
  • Accurate
  • Complete
  • Durable
  • Corroborated
  • Version Based
  • Accessible
  • And Authorized

Change Control

Change to GMP documentation, equipment, processes, systems, instrumentation, test methods, etc. are required to be controlled under a formal change control program.

This program must consist of Quality oversight to review the proposed changes, evaluate the potential impact of the change, determine any potential risk to product quality, and to establish the required level of supplemental validation/documentation required for the change.

In many instances, changes will also require submission to the Health Authority for approval of the change.

For example, changes impacting the submission documentation are subject to post approval change guidances according to the Health Authority regulations.

Change Control is a critical aspect of the GMP systems.

If you want to learn more about cGMP or if you want to evaluate our eLearning module for your company you can find more information here.



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