HEPA Filter Integrity Testing
In-situ HEPA filter integrity testing using DOP (Dispersed Oil Particulate) and DPC (Discrete Particle Count) methods for healthcare, pharmaceutical, and industrial clean environments.
Home > Services > HEPA Filter Integrity Testing
What Is HEPA Filter Integrity Testing?
HEPA filters are the last line of defence in critical ventilation systems, removing 99.97% of particles at 0.3 microns. But a filter is only as good as its seal. A single pinhole, a damaged gasket, or an incorrectly seated filter can allow contaminated air to bypass the media entirely.
Integrity testing confirms that each installed HEPA filter is free from leaks and performing as specified. It is a requirement of HTM 03-01 for healthcare critical ventilation and essential for pharmaceutical cleanrooms, laboratories, and any environment where airborne contamination control is critical.
Testing Methods
DOP (Dispersed Oil Particulate) Testing
An aerosol challenge is introduced upstream of the filter, and a photometer scans the downstream face to detect any penetration above the acceptable threshold. This is the traditional method and remains widely used in healthcare.
DPC (Discrete Particle Count) Testing
A particle counter measures actual particle concentrations upstream and downstream of the filter to calculate penetration. This method provides quantitative data and is increasingly specified in modern standards.
We carry out both methods and advise on the most appropriate for your application and compliance requirements.
Applications
- Operating theatre UCV canopies
- Isolation room supply systems
- Pharmacy aseptic suites
- Sterile services departments
- Microbiological safety cabinets
- Pharmaceutical cleanrooms
- Research laboratories (CL2/CL3)
- Industrial clean environments
Frequently Asked Questions
How often should HEPA filters be integrity tested?
At every filter change, after any system modification, and as part of annual HTM 03-01 Part B verification. Some facilities test more frequently depending on risk assessment.
What constitutes a HEPA filter failure?
Any penetration above 0.01% of the upstream challenge concentration at any point on the filter face or seal constitutes a failure requiring remedial action.
Can you replace failed filters?
Yes. If integrity testing identifies a failed filter, we can supply and fit replacements and re-test to confirm the installation is leak-free.
Book HEPA Filter Testing
DOP and DPC integrity testing, UK-wide.