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18 May 2021

SIC Laboratory Equipment Repair

Cleanrooms are environments in which several parameters are controlled, monitored, and maintained.  With an increasing emphasis on maximizing product  yield, improving quality control, and ensuring safety, companies throughout many industries are looking to install cleanrooms or controlled environments in their facilities.

There are a lot of determining factors involved in choosing a cleanroom classification and every industry has a default standard to start with.  In medical device packaging, the default classification is ISO 7 (or class 10,000) cleanroom.

Choosing a cleanroom to meet your needs
the cleanroom you may need is going to be determined by several different factors. 
1. Industry Standards

2. Customer Requirements

3. Government Regulations

4. Ease of Cleaning

5. Restriction of Access

6. Particulates
7. Temperature
8. Humidity
9. Microorganisms

Once all these factors are considered, you can then make accurate choices regarding the scope of the cleanroom operation you should implement.  Today we are going to focus on how particle size impacts classifications.

How Particle Size Impacts Classification

One of

 the most important factors to determine when constructing a cleanroom is what size of particle will need to be filtered out.  Often times, people look at the cleanroom classification and they go to the lowest level particle count to determine what classification they need.

In a cleanroom environment, air particles are measured in microns.  Once micron equals on-millionth of a meter.  Micron-sized particles are small than a living cell and can be seen only with the most powerful of microscopes.

How large is a micron
A strand of human hair can vary in width from approximately 20-180 microns, while the average size is typically 50-70 microns.   Once small dust particle seen in a ray of sun equates to approximately 60 microns.  Pollen is approximately 30-50 microns, while bacteria are approximately 2-10 microns in size.   A typical indoor air sample may contain anywhere from 500,000 to 1 million particles per cubic foot of air, and the Human eye cannot see objects less than 50 microns in size.

A typical cleanroom is designed to keep the outside environment from getting in.  Once an environment has been built, the two things that cause contamination in it are the people and the process.
What contamination is generated by people and what contamination is generated by the process?

To maintain a cleanroom environment, you need to focus on:

  1. Air handling and filtration
  2. Personnel training
  3. Proper cleaning equipment

A High Efficiency Particulate Air (HEPA) filter controls the particle size.  Used for ISO Classes 2-9, HEPA filters trap particles that are 0.3 microns and larger.  To achieve ISO Class 1, you would use an Ultra-Low Particulate Air (ULPA) filter for smaller particle sizes.

To meet cleanroom specifications, each ISO Class requires a different:

  1. Airflow type
  2. Airflow velocity
  3. Air changes

All employees should undergo extensive training in cleanroom standards.  Before entering or exiting a controlled environment, workers should pass through an airlock.  Personnel will also need to wear special gowns and gloves. These will trap contaminants caused by the human body.


Keep your cleanroom compliant by following the appropriate cleanroom standards outlined for your specific environment.  Do not forget to make adjustments for any changes to the guidelines that may arise.   Doing so will not only ensure compliance but also help protect manufacturing equipment, products, and even personnel from harmful airborne particulates. 

Disinfectants Used in Cleanrooms

There are very stringent protocols governing what comes in and out of a cleanroom, and also for disinfecting the cleanroom environment. Ensuring cleanliness in a cleanroom is an essential part of maintaining the cleanroom’s productivity and efficacy. For this vital task, choosing the wrong disinfectant can have catastrophic results.

Criteria for cleanroom disinfectants:

  • Non-reactivity:any disinfectant used in a cleanroom environment needs to be as chemically inertas possible to avoid any chemical reactions and possible contamination. This is also why cleanroom disinfectants that have been opened and used need to be utilized or removed within 30 days. This will help avoid contamination, even though this is almost impossible.
  • Low residue:all disinfectants leave residue. Cleanroom disinfectants need to limit that to a minimum while maintaining effectiveness, so a low residue and highly effective disinfectant is the norm in a cleanroom environment.
  • Sterile:it goes without saying that just like anything else entering the cleanroom, sterility of a disinfectant product is a must.
  • Effectiveness:disinfectants need to be effective at cleaning and destroying any microorganisms they come into contact with, be it bacteria, fungi or any bio-contaminant. Chlorine-based disinfectants tend to dominate the market due to their proven efficacy in eliminating biohazards, but there are alternatives, depending on the desired properties of the disinfectant.
  • Fast acting:disinfectants need to act fast and evaporate quickly to avoid trapping any particles while drying out.
  • Safety and environmentally friendly:disinfectants need to meet environmental guidelines and pose no hazard to users.
  • User-friendly:disinfectants and/or disinfectant-impregnated wipes need to be ready to use and easy to handle, with no complicated intermediate preparation phase.

After choosing the right disinfectant for the cleanroom, it is important to assess the best maintenance and cleaning protocol. This will be dependent on operational activities, the level and type of contamination threat, and the qualities of the disinfectant used. Regular controls and checks for any bio-contamination are essential for assessing the efficacy of both protocols and disinfectants.


To learn more about Scientific Instrument Center (SIC) and our Innovative Solutions visit us
Here you can read more about our services or call 800-686-8965 for quick “Same day or Next Morning” on site scientific equipment maintenance services. 

Our skilled staff members understand the nuances of instrument calibration and the manufacturers train our technicians, so any inspections we make mean your equipment is to quality standards.   For more than 30 years, SIC has served businesses that use a wide variety of diagnostic and scientific equipment.   As a leader in Scientific Equipment Reaper and medical device calibrations, we work with many corporations, universities, and hospitals.  We are specialists.



Get a free consultation.  Call (800) 686-8965