continuous environmental monitoring is your best option to lower risk, as highlighted in the latest guidelines

Effective environmental monitoring requires a combination of prepared media, equipment and validation processes.

Under the latest draft revision of EU GMP Annex 1, environmental monitoring is more important than ever before. As pressures mount to increase efficiency while lowering risk of any contamination, in process environmental monitoring is now recommended.

Cherwell Laboratories supply all the specialist materials and equipment you need to ensure your cleanroom standards are maintained to meet the most stringent regulations. We can also help you create an EM program specifically for your premises.

For best practice, a combination of static and active air samplers, together with accessories to ensure precise data collection is required. Regular instrument calibration maintains top performance levels and your data remains 100% reliable.


Let's discuss your requirements

Environmental monitoring equipment explained

A combination of air sampling methods help reduce contamination risk

Select quality assured culture media

Used in cleanrooms, isolators, operating theatres, offices, factories and waste processing sites

Petri dishes are widely used to collect air samples passively and also in air samplers. Contact plates for environmental monitoring contain raised agar for surface sampling and in air samplers. Make sure your media is quality tested.

Active air samplers

These air samplers draw air onto a poured media plate. Used widely in areas of various grades

Air samplers that actively draw air over culture media are widely used in conjunction with settle plates and other methods for more accurate data. These instruments should be calibrated regularly.

Tailor your program to fit

Reproducibility is everything. Use accessories to make sure your poured media are placed accurately

Appropriate location for environmental monitoring equipment and static air sampling is critical for accurate, reliable results. Stainless steel stands are ideal for use in critical areas.


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FREQUENTLY asked questions

About Environmental Monitoring

Our environmental monitoring requirements have changed. Can you help us create new processes?

Yes. We have almost thirty years' experience with helping pharmaceutical and associated industries deliver environmental monitoring processes critical to the manufacture of heavily regulated products.

We supply every component you need to create environmental monitoring processes. We also offer bespoke formulations, accessories and even packaging solutions for organisations with very particular needs.

Get in touch today. Let's discuss your requirements.

Do I need to store my prepared media in the fridge?

The majority of our prepared media can be stored in ambient conditions, not exceeding 25ºC. There are only a small number of very specialist products that require different storage conditions.

We have never specified refrigeration as a storage condition for our general media as this causes excess condensation and can result in very wet agar, rendering it impossible to use.

What is the maximum exposure time for settle plates?

Settle plates are used to monitor the level of viable particles in the environment through a process of passive air sampling. A viable particle settles on agar plates at a rate dependent on its characteristics and the airflow in the environment.

EU GMP Guide Annex 1 has recommended that 90mm settle plates can be exposed in cleanroom environments for up to 4 hours. However, agar plates may dry out during long exposures where the rate of air exchange is high. So, it might be necessary to use deep filled settle plates, or replace the settle plate after a shorter time to ensure satisfactory growth promotion after exposure.

How much air should we sample?

Typical requirements suggest 1,000 litres per air sample in high risk areas, such as: grade A filling lines, grade B clean rooms, operating theatres etc. As the criticality of the area reduces, the sample size can be reduced. The aim is to achieve a representative sample; so where higher counts would be expected, a smaller sample produces a more realistic number of cfu to count.

Should I use contact plates or Petri dishes in my air sampler?

SAS samplers were originally designed for Contact plates, however, a Petri dish option has been available for a number of years. It is really a personal choice, although this should be decided at time of purchase, as the sampler will be specifically configured for the plate type chosen. There are advantages for each version and we would be happy to discuss your specific needs.

cherwell are environmental monitoring experts

Prepared media, equipment, accessories and services in one place


Getting it right from the start

Tell us about your business and we can help design the best EM solutions for you including prepared media, equipment and accessories


Quality assured products

Our products all come with quality assurance certification, manufactured in our ISO 9001 registered facility, delivered to order


Flexible service options

All formulations, consignment sizes and bespoke requirements considered. Our flexible service is tailored to your business


get our latest environmental monitoring ebook

The Environmental Monitoring Processes and Validation Guide

Understand the key changes and challenges of the EU GMP Annex 1 draft revision.

What will it mean for your environmental monitoring processes?

Download Guide

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