Cleanliness and air filtration are vital when maintaining sterility levels in laboratories, manufacturing facilities, hospitals, and compounding pharmacies. This also applies to a laminar flow hood or clean bench. Maintaining cleanliness inside the hood using proper cleaning methods and a regular maintenance schedule will ensure your laminar flow cabinet provides safe and accurate results.
Cleaning a laminar flow hood sounds straightforward, but there are plenty of factors to consider, such as ensuring you are cleaning correctly to prevent contamination and maintain the integrity of a sterile environment. Here are our top cleaning tips:
Preparing the hood for cleaning
Before you begin cleaning the laminar flow hood, make sure it is turned off and disconnected from the power source. If you have equipment in the hood, this should be removed, along with any supplies or debris from the work surface. Then, gather your cleaning materials, detergents and personal protective equipment (PPE).
Using the right cleaning materials, detergents and PPE
It is recommended to use lint-free cloths, as this prevents debris from the cleaning cloth from entering the laminar flow hood. Larger cloths can be folded into quarters so that a clean piece of cloth can be used to clean each side of the hood. If working in a cleanroom environment, check that the chosen cloths are appropriate for cleanroom use.
Only use a cleaning agent compatible with the hood’s material composition. Commonly used cleaning solutions are IPA, ethanol, and distilled water. Bleach solutions are a common choice for cleaning and disinfection. However, bleach is corrosive and not recommended for stainless steel hoods. If bleach must be used in a stainless steel hood, great care must be taken to thoroughly rinse away all of the bleach residues using sterile water or 70% alcohol to reduce the chances of corrosion and prolong the life of the hood.
Wearing the correct PPE, such as cleanroom gloves, eye protection, and a lab coat, is essential to ensure protection from potentially hazardous substances.
The right way to clean
To prevent recontamination, it is important that you clean the hood in an order using the correct method. You should always clean from back to front, top to bottom. Beginning in the top back corner, wipe down the entire span of the wall surface with long, side-to-side motions. Do not wipe in circular motions for efficient cleaning; wipe in one direction using parallel overlapping strokes (try and overlap strokes by 25%, preventing you from missing any spots). Use a clean cloth for each new section and pay particular attention to corners, edges and hard-to-reach areas where contaminates can accumulate.
Never spray detergent directly inside the hood. Laminar flow hoods contain filters, sensors, and electrical outlets that can be damaged when sprayed. In hoods with grates, cleaners can pool below the grate and dry, damaging the hood’s surface or leaving a residue that is difficult to remove. Instead, spray cleaners onto the lint-free cloth or gauze until it is wet but not dripping, or use an impregnated cleaning wipe.
Do not over-scrub
Harsh scrubbing can damage the protective layer on the hood’s surface and shorten the equipment’s life. Scrubbing can also introduce small scratches that are difficult to clean and disinfect. These scratches can become contaminated with microorganisms and act as a source of product contamination. For this reason, abrasive cloths or materials should never be used to clean a hood.
Replacing HEPA filter
The operator must properly maintain the HEPA filter and blower unit to ensure the efficient functioning of the laminar flow hood. In most cases, the HEPA filter cannot be cleaned and should be replaced according to the manufacturer’s recommended schedule. The exterior surfaces of the blower unit can be cleaned using a soft, lint-free cloth and a mild detergent. Be careful not to introduce any liquid or cleaning agent into the blower unit, as this will damage the HEPA filter.
Documentation
Operators should plan to clean laminar flow hoods on a regular schedule in accordance with applicable standards and written standard operating procedures (SOPs). Each hood cleaning activity should be clearly documented to ensure you and your team maintain this schedule. Be sure to include the date (and time, if necessary), the type of cleaning that was completed (wipe down versus deep clean), any cleaning agents that were used and if filters were replaced (if applicable). This documentation provides a traceable history and demonstrates compliance with cleanliness and sterility requirements. It will also make planning for deep cleans easier to make efficient use of time and workspace.
Ongoing maintenance and performance checks
Regular maintenance is key to continued performance. Not only does it ensure a safe working environment, but it also prolongs the life of your laminar flow hood. Periodically inspect the hood for any signs of wear, damage, or malfunction. Also, check the airflow pattern, monitor the pressure differentials, and test the hood’s functionality according to the manufacturer’s recommendations.
Any issues should be addressed promptly to maintain the hood’s integrity and effectiveness. For support with your AirClean System, contact support@syngene.com.
We hope that these 7 top tips will help you when writing and executing laminar flow hood cleaning SOPs. Proper and regular cleanings are necessary to prevent microbial and cross-contamination between procedures and users, ensure reliable data and test results, promote safety, and maintain product quality and ISO compliance.
For your cleaning schedule download our template here:
