Quick Tips for Fume Hood Exhaust Monitoring Part 2

Proper airflow is vital to personnel who are working with corrosive, hazardous, or volatile materials in a cleanroom. Safety hinges on proper fume hood exhaust monitoring; it alerts workers when the airflow drops below calibrated levels. In Part 1, we discussed some available options in fume hoods. With a fume hood selected, you can focus on maintenance, replacing equipment, and selecting the monitoring system.


Regular maintenance will likely be an annual or semiannual certification consisting of a velocity test with a thermal anemometer at predetermined points. The points depend on the size of the sash opening. The certification also includes calibrating the alarm and performing a smoke visualization test to prove airflow direction and smoke containment. In addition to certification, facility personnel should carry out scheduled checks on the blower motor belt.

Replacing Equipment

Your fume hood monitor does not need to be replaced until the system doesn’t function any longer or it doesn’t calibrate properly.

Selecting the Monitoring System

The monitoring system is obviously a critical part of the fume hood as it is what will tell you when levels are dangerous. Your choice will ultimately depend on how much data you want to receive. Some systems will set off an audible and visual alarm when velocity drops a set percentage; others will actually give a read out of the velocity. Your customer may require the read out for documentation. There are monitors that don’t give both alarms, but your safest bet is to go with one that has both the audible and visual alarms.

Remember that when installing your fume hood, you need to look at the layout of your lab. You don’t want supply vents or filters directly in front of the hood. It’s best to have a full ASHRAE 110 test at the initial certification. Additionally, it is best to have your fume hoods on dedicated exhaust systems. If one unit needs an adjustment, it usually requires a rebalance of any other hoods within a shared system.

For cleanroom certification and validation, contact the experts at Gerbig Engineering Company: 888-628-0056 or info@gerbig.com.

Quick Tips for Fume Hood Exhaust Monitoring Part 1

What kinds of options do you have available when selecting a fume hood for your cleanroom? What else do you need to know?

When working in a cleanroom with corrosive, hazardous, or volatile materials, sufficient airflow is critical to personnel safety. Calibrated exhaust monitors typically have audible and visual alarms to alert workers when the airflow drops below calibrated levels. In addition to monitoring this airflow, exhaust monitor alarms can also indicate that there is a problem with the pressure. As you can see, it is imperative to have calibrated exhaust monitors for your fume hoods. We offer some quick tips on choosing and maintaining your fume hoods. First, a few words about your options:

Selections in Fume Hoods

There are numerous options for fume hoods. Among these, you will find two different airflow valve setups:

Variable Air Volume (VAV) – This can be programmed to either adjust air velocity based on where the sash height is or regulate it regardless of where the sash height is.

Constant Volume Valve (CV) – The hood is designed so that it’s worked in at a specific velocity and a specific sash height. When the sash is raised past the set point, the velocity will drop; when the sash is lowered, velocity increases.

The other variations revolve around size, material, and sash opening setups. Some of the materials available include coated wooden units, polymer materials, and coated or raw stainless. Sizes vary greatly. You can find sash openings that are horizontal, vertical, a combination, and walk-in.

Knowing how many options you have available will help you understand exactly what you need to determine before selecting the fume hood itself. In next week’s post, we will continue with tips on maintenance, replacing equipment, and selecting the monitoring system.

For cleanroom certification and validation, Gerbig Engineering Company provides expert services. Call us at 888-628-0056 or email info@gerbig.com.

Optimal Type 2 Water Quality for the Cleanroom

You have numerous options for pretreatment methods for pure water, but what is the best combination to produce Type 2 water?

In our last post, we covered the six methods for pretreating water to make it pure for cleanroom purposes. This pretreatment is a vital stage in water purification, but it’s often overlooked. None of the methods will completely remove contaminants on its own, so it’s imperative that you find the right combination. While the exact best fit for you will depend on the application, there is one combination that is often the best to create Type 2 water: Reverse Osmosis (RO), and Electrodeionization (EDI).

To recap, RO is extremely useful in the first step of the purification process. It removes the majority of broad range of contaminants. Its efficiency, however, does vary among contaminant types.

EDI combines direct electrical current with ion exchange resins as well as selective semi-permeable anionic and cationic membranes. This technology deionizes water effectively, as the electric current continuously regenerates the ion exchange resins.

Using these methods together produces water with consistently low levels of ion and TOC. Having such a consistent quality makes it ideal for producing ultrapure water, as other methods tend to result in polished water that has fluctuating levels of contaminants. These kinds of fluctuations compromise any data that’s pulled using trace and ultra trace analyses.

Of course, once you have chosen your water purification methods, be sure to properly train personnel on use and maintenance of the technology and systems. Consistent monitoring will also ensure you are meeting compliance.

For cleanroom validation and/or certification, Gerbig Engineering Company provides quality services that will help you maintain the success of your business. Call us to discuss your needs at 888-628-0056 or reach out via email: info@gerbig.com.

6 Pretreating Methods for Pure Water in Cleanroom Labs

Here is a look at the 6 kind of methods used to pretreat water in the purification process necessary to use it in a cleanroom laboratory.

There’s water purification that produces Type 1, or ultrapure water, but equally important is the pretreatment step that results in Type 2 water. Pretreatment actually removes most of the contaminants in tap water. This step needs to be relied upon consistently, yet it is often overlooked. To ensure your water is purified to the highest possible standard, be sure to use a combination of the following technologies:

  1. Distillation. This removes a wide range of contaminants, but it requires large volumes of tap water and electrical energy. This method of purification is relied on much less today as contaminants are carried into the condensate.
  1. Reverse osmosis. The efficiency of this method varies among contaminants, but it is capable of removing the bulk of most of them.
  1. Ion exchange resins. This effectively removes dissolved inorganics (ions) and charged organics. It doesn’t remove neutral organics, bacteria, or particles, however.
  1. Electrodeionization. This process deionizes water while the ion exchange resins are continuously regenerated by the electric current in the unit.
  1. Activated carbon. There are two forms of this: natural and synthetic. Natural activated carbon has a high concentration of ionic contaminants. It’s only used as a preliminary step to remove chlorine from water. Synthetic activated carbon is much cleaner, and used to remove trace organics of low molecular weight.
  1. Germicidal UV. Ultraviolet radiation inactivates microorganisms and prevents microbial growth and contamination. This is a widely used germicidal treatment for water.

In our next article, we will discuss the best combination of methods to produce Type 2 water. If you have questions about cleanrooms or need certification or validation, contact Gerbig Engineering Company. We care about your success. 888-628-0056; info@gerbig.com

Cleanroom Leadership Personalities: Are you Driving Success? Part 2

Check out whether your cleanroom management style will help or hinder the success of your employees and your business.

Knowing your own management strengths and weaknesses is important for any leader. You can’t truly evolve until you understand who you are, how you thrive, and what sets you back. We began explaining Randy H. Nelson’s four personality types for leaders in our last article. Here we will explain what the remaining two are and how people with these personalities can best succeed.

Reflexively Pessimistic: This person is always ready for a crisis. This person is a survivor; however, the constant focus on what can go wrong interferes with this leader’s ability to grow. He or she has no strong foundation of how to manage when times are good. Staying the course on a good day is just as important as righting the ship in a storm. A beneficial exercise to help this leader would be one similar to the one explained for the ever-optimistic leader. He or she should list the strengths and weaknesses of the major facets of business he or she leads. Following, this person should present this to colleagues with a focus on positive comments and forward-thinking plans.

Steady-Proactive: What Nelson says about this group is: “These leaders are clear in what they know and don’t know. This person has moved beyond a revenue-only focus and now devotes time and effort to understanding what boosts stock value, using this knowledge to push the valuation ever higher.” On the flip side, this kind of style doesn’t allow employees to relax and enjoy the moment. An exercise that would help this type of leader would be to have him or her come up with ways to stop and celebrate successes at least once a quarter.

Cleanroom managers: when it’s time for cleanroom validation and/or certification, do you use a company with 30 years of proven experience? Contact the experts at Gerbig Engineering Company when you need competent professionals with stellar customer service. 888-628-0056; info@gerbig.com

Cleanroom Leadership Personalities: Are you Driving Success? Part 1

Does your personality help or hinder your employees’ and company’s success? Cleanroom managers: check it out.

Just as with all jobs, CEO and management positions tend to attract certain types of people. Some personalities work well in roles like these, and they are able to help the company thrive. Others struggle to succeed. Often times, managers don’t actually know themselves well enough to know the difference.

According to reputable business leader Randy H. Nelson, there are four major personality types for leaders. Here are the first two descriptions of personalities and what would help them succeed.

Urgent/Reactive: This person is not proactive, but rather waits until the last minute to take action. As Nelson says, “This business personality creates and thrives on an almost crazed atmosphere, where he or she can ride to the rescue, put out the fire, be everybody’s savior, then move on to the next problem. In other words, fix it and forget it. It’s characterized by action without introspective vision and premeditated guidance.”

According to Margery Weinstein, who writes for trainingmag.com, these kinds of leaders lack introspection. For them, taking a personality test to gain personal introspection, and preparing a presentation of their vision for the company to gain professional introspection, would really strengthen this personality as a leader.

Ever-Optimistic: This person has a can-do attitude that is great for encouraging confidence and morale. He or she is enjoyable to be around and can propel motivation. However, when the going gets tough or the luck runs out, this person often doesn’t know how to react. Additionally, this person finds it difficult to deal with employees who are skating by.

Weinstein suggests that managers with these personalities list both the strengths and weaknesses of the major facets of business they lead and present it to a work group to collaborate on a plan to improve.

Check out part two to read about the remaining two personality types. If you’re a cleanroom manager who needs to stay ahead when it comes to certification or validation, contact Gerbig Engineering Company. Our experts have 30 years of experience. Contact us at 888-628-0056 or info@gerbig.com.

Testing Compressed Air Lines – Medical Device Manufacturing

If you’re a medical device manufacturer, you need to clean the air systems that clean your components. Here is some advice.

Compressed air is used in many applications for medical device manufacturers. While they are generally used to eliminate contaminates, the compressed air system itself can harbor microorganisms. This can adversely affect the product, so it’s important to routinely test your air lines.

Things to consider when scheduling your periodic testing include:

  • Increases or decreases in production schedules
  • Changes in the seasons
  • Changes and modifications made to equipment
  • Any hardware or dryers/filters replaced
  • System inactivity

The actual test should use air impaction onto growth media by reducing the compressed air pressure using a built-in or external regulator. Then attach a flow meter, adjust the flow to a suitable rate, and attach the prepared Petri plate with the air impaction sampler.

Your test equipment will likely include a Slit Sampler, or slit-to-agar sampler. This puts the Petri plate on a rotating stage to impinge the organisms onto the agar. The plate is then incubated so the microorganisms can grow.

There are a few things to consider when developing a sampling plan:

  • A longer sampling time is appropriate when the air system is static
  • A shorter sample time is appropriate when the air system is in use
  • Broad spectrum, non-selective media will enable the growth of too many organisms and overwhelm the process
  • Selective media, on the other hand, can potentially limit overall growth, giving quantitative counts.

A broad-spectrum agar like Tryptic Soy Agar (AGA) is a recommended medium for the growth of non-fastidious organisms. If you’re trying to isolate a certain type of microorganism, you can use something like Subouraud Dextrose Agar, which cultivates fungi.

If you need cleanroom certification or validation, including a Validation Master Plan, contact Gerbig Engineering Company: 888-628-0056; info@gerbig.com.

Quick Checklist for Cleanroom Cleaning Costs

Here’s a checklist for your cleanroom cleaning system costs. Use this as a guideline for budgeting with your new system.

We post a lot of information about cleaning your cleanroom. It is a complex and involved aspect of compliance and safety. Things to consider vary from the cleanroom itself to the parts inside of it. You can browse some of our topics here.

One crucial aspect of any new cleaning regimen is the cost. You need to know what to anticipate as far as expenses are concerned. These will include initial one-time costs as well as ongoing. The type of system you need depends on your specific application, so exact materials and costs will vary. However, you can get an idea of what you need to budget for by using this checklist put out by Controlled Environments in “Cleaning Costs Checklist” by Mike Jones. Here is how the MicroCare Corp expert lays it out.

Capital Costs – One-Time Costs

  • The actual cleaning system
  • Architectural planning and site engineering
  • Construction
  • Insurance and freight
  • Electrical
  • Plumbing
  • Ventilation
  • Set-up of the actual system
  • Cost of capital


  • Will be a cost per square foot
  • Size of the machine(s)
  • The work space multiplier

Throughput Calibration Factors include:

  • The cycle time
  • The boards per cycle and maximum boards per hour
  • Number of operating hours required each day
  • The stand-by hours each day

Operating Costs

  • Water and electricity
  • Consumables like filters
  • Solvent –
    • Losses
    • Disposal
  • Labor –
    • Operator cost per hour
    • Inspection and re-cleaning per hour
    • System maintenance per hour

This checklist will get you started in understanding the costs you need to anticipate for a cleanroom cleaning system. For cleanroom validation or certification, trust Gerbig Engineering Company. Our experts understand compliance for cleanrooms in several industries. Contact us at 888-628-0056 or info@gerbig.com.

Three Tests for Disinfectants for Cleanroom Validation

You need to control fungal contamination in your cleanroom, and you need to test the disinfectants for validation. Here are three to consider.

Controlling fungal contamination in your cleanroom requires cleaning and disinfection procedures. Your disinfectant application is a critical step that needs validation. Since many agents that are effective against vegetative fungi aren’t effective against fungal spores, it’s necessary to conduct a series of tests to demonstrate your agent’s efficacy. Here are three testing methods to consider.

  1. Suspension tests. These are especially valuable for finding how much time is needed to reduce organisms to an acceptable level. However, they don’t reveal any variations in efficacy that happen when disinfectants are applied to different surface types. The test procedure is to suspend the microorganism in an appropriate dilution of the test disinfectant. At designated time intervals, samples are removed for viable counts. The test is conducted at room temperature.
  1. Carrier tests. These are specific to hard-surface disinfection agents, and they’re performed under the conditions that match your facility’s specific application. Typical cleanroom surfaces are stainless steel, but can also include terrazzo flooring, vinyl, epoxy, and glass.
  1. Statistical comparisons. While both of the above tests are quite reliable in evaluation a disinfectant’s efficacy under lab conditions, they guarantee results in your actual cleanroom environment. To address this, you need to perform statistical comparisons of the frequency of isolation and the numbers of organisms isolated before and after a new disinfection program is implemented. Trend the environmental data over the course of a year to find seasonal variations that may cause facility or maintenance issues.

When it’s time for cleanroom validation, trust the experts at Gerbig Engineering Company. We’ve provided cleanroom validation, certification, and construction for thirty years. Contact us at 888-628-0056 or info@gerbig.com.

Methods for Testing Container Closure Integrity : Cleanroom Products – Part 2

Container closure integrity is a must for drug manufacturers. Here are the last 2 of 5 common methods to test this integrity

As mentioned in part 1, container closure integrity (CCI) is paramount for the entirety of the shelf life of any drug product. There are numerous ways to test CCI. In part 1, we discussed dye ingress testing, vacuum decay, and headspace analysis. Here we will wrap up with the final two most popular methods: helium leak and high voltage leak detection.

Helium Leak. While the previous methods discussed are not extremely sensitive, this test is the most accurate, giving the most reproducible results. Helium is one of the safest gases to use for such a test, and the vials or syringes can be filled manually or arrive with helium in them.  A mass spectrometer that only detects helium ions picks up the rate of helium leaking from a container. Vials can contain liquids or lyophilized product; syringes must be empty. The helium does destroy the product, but this test can pinpoint a leak, and it can be conducted in cold temperatures.

High Voltage Leak Detection (HVLD). This method is very practical for stability studies, biologics, and containment systems holding liquid with no headspace. A high-voltage current is applied to the liquid in the container, and a voltage differential identifies an integrity breech. It’s a non-destructive method that produces rapid results and requires little operator skill.

The right CCI test will depend on your specific application and needs. For cleanroom validation or certification, contact Gerbig Engineering Company. We have thirty years of experience in the cleanroom industry: 888-628-0056; info@gerbig.com.

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