Data Centre Cleaning Standard ISO 14644-1 Class 8

IT Cleaning Ltd Magazine Article published in Cleanroom Technology

ISO 14644-1 2015 Class 8… International Standard for Clean Rooms Clean Zones and Controlled Environments.

A Standard For Cleanliness for all types of Controlled Environment including Data Centre, Data Rooms, Server Rooms and Comms Rooms is ISO 14644-1 2015 Class 8, plus all accessible surfaces free from dust. This is currently best practice.

Believe it or not, there are data centre cleaning standards, based on the international standards for cleanroom, clean zones and controlled environment (Data Centre’s / Data Halls / Data Rooms are controlled environments) this is ISO 14644-1. The ISO 14644-1 2015 series of standards (14644-1 to 14644-12) are a series of documents that establish various classifications for cleanliness as well as methods for testing compliance, test methods, design/constructions/start up considerations, and others, fro controlled environments. Click on ISO standard to see standards. Data Centre Cleaning Standards, Data Room Cleaning Standard and Comms Room Cleaning Standard are based on the same ISO 14644-1 2015 Class 8 standard, as these rooms are controlled environments. ISO 14644-1 2015 Class 8 is often misnamed, by specifiers, as a Clinical Clean.  ISO 14644-1 1999 has been withdrawn and replaced by ISO 14644-1 2015.

“Contamination has been the indirect cause of more IT downtime than all the fires, floods, hurricanes, earthquakes, and disgruntled employees combined.” – Jon William Toigo, Disaster Recovery Planning, Third Edition. 

Less than optimally clean hardware can severely impact data centre performance. Sub-microscopic particulates can interfere with your critical equipment’s electronics, leading to hard-to-troubleshoot problems and even data loss. “Datacom manager focus most of their energies on the physical structure and performance of the datacom infrastructure environment (cooling, power, and equipment). However, today’s intricate and sensitive information technology equipment requires certain levels of control of particulate contamination. This is often overlooked and left unchecked to disastrous effects”. ASHRE 2009. ISO 14644-1 2015 Class 8 is the solution.

Dissipating heat is essential to data centre operations, which means maintaining a steady airflow through the data centre. But this constant airflow can bring with it dust, dirt, and other types of particulates that find their way into your equipment’s delicate electronic innards. No matter how well your filtering systems work, every now and then it is necessary for data centre cleaning or computer room cleaning to be done. Indeed most equipment manufacturers state that data rooms should be cleaned regularly by a professional data room cleaning company.

“Perhaps the most important step to take to control contamination, is to contract with a reputable computer room maintenance company, to perform routine cleaning”. John William Toigo, Disaster Recovery Planning Third Addition.

The yardstick for measuring cleanliness is the amount of microscopic particles found per cubic metre of air. These particles range in size from 5μm (micrometre: a millionth of a metre) in diameter down to 0.5μm in diameter. Obviously, the larger the amount of large particles in an environment, the visibly dirtier the environment is. On the other hand, a small amount of very small particles means an extremely clean environment.

The ISO 14644-1 standard sets up ISO classes from 1 through 9; ISO Class 1 the most stringent, for example, allows only Ten particles at 0.1μm and two at 0.2μm per cubic metre’s of air. Class 1 is the ultimate in cleanliness, a tremendously stringent standard that only highly controlled environments, such as clean rooms in microprocessor fabrication or drug manufacture, can achieve.

The data centre standard that most data centres (which are controlled environments) need to be kept clean too is ISO 14644-1 Class 8 standard or better. Class 8 allows 3,52 million 0.5μm particles per cubic metre. Class 8 is often referred to as a 5 Micron Clean or Clinical Clean. Indeed the following Cisco, Chapter 3, Sun and Oracle now all state what the acceptable levels of contamination are for their equipment. All three hardware vendors now state that “their equipment must be kept in a data centre which has been decontaminated to a sufficient level on the ISO 14644-1 Clean Room and Controlled environment scale” This is Class 8 or better. This suggest that their OEM warranty will not cover equipment damaged by dust.

IT Cleaning specification is ISO 14644-1 2015 Class 8 or better plus all accessible surfaces to be free from dust (5 Micron Clean). This is ISO 14644 Class 8 for air particulate plus all accessible surfaces free from dust. As part of our SCOPE we will carry out a particulate survey to ISO 14644-3 requirements. After the data room cleaning we will issue a certificate of conformity to show what ISO 14644 Class the room has achieved. These certificates are invaluable for internal and external audits plus most OEM’s may require them after a contamination event to allow them to re apply their warranties. For information on Data Centre, Server Room & Comms Room Cleaning.

ISO 14644-2 2015 states that to achieve the ISO 14644 Class 8 standard the room must be cleaned at no less than 12 monthly intervals.

For an example of a validation report and certificate follow the link Validation to ISO14644 Class 8 or 7  

“Particulate and gaseous monitoring is a good idea for all data centers but should be mandatory when using air-side economizers”.Joseph Prisco IBM. A 2007 study by Pacific Gas and Electric, along with Lawrence Berkley National Labs, (for full study) compared particulate concentration in data centres with economizers (Free Air) cooling systems against those who introduce minimal, if any outside air. The results were as expected. Data Centres which use economizers have higher particulate concentrations in them than those who use traditional cooling systems. This suggests that whilst free air is economic, it may bring problems of its own, which should be understood prior to installation. Filtration and cleaning regime should be discussed.

We are trained and able to offer Validation services and Airborne Particulate Monitoring as a one off or a regular service. Surveys are carried out as per ISO 14644-3 “Testing of Cleanrooms and associated controlled environments” (data centres are controlled environments). Using a state of the art Solair 5100+ particulate counter we are able to determine the threat to your critical environment. We use ISO 14644-1 Class 8 or better as our bench mark for computer rooms and data centres.

International Standards for Cleanrooms, Clean Zones and Controlled Environments


Number of Particles per Cubic Metre by Micrometre Size

0.1 um 0.2um 0.3 um 0.5 um 1 um 5 um
ISO 1 10
ISO 2 100 24 10
ISO 3 1,000 237 102 35
ISO 4 10,000 2,370 1,020 352 83
ISO 5 100,000 23,700 10,200 3,520 832 29
ISO 6 1,000,000 237,000 102,000 35,200 8,320 293
ISO 7 352,000 83,200 2,930
ISO 8 3,520,000 832,000 29,300
ISO 0 35,200,000 8,320,000 293,000

For a free site survey and quotation or further information please contact Stephen Yates 0870 0052581 or

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