Here's a snippet from another forum where Shane answered virtually the same question. Hope this helps answer your question...
If your Festool CT Dust Extractor has been used for the purposes of EPA RRP work, you must use the proper personal protective equipment (PPE) while performing main filter replacement and dispose of the filter and filter bag accordingly to EPA RRP guidance and following the local jurisdiction, state, and local requirements.
This is highly subjective depending on degree of use, including frequency, duration, and conditions. Foremost, we strongly urge the use of pre-filter bags which filter dust down to 5 microns, helping to prevent loading of the main HEPA filter, and protect the filter from damage from larger particles of dust and debris. The RRP rules do not provide guidance on this matter, and each different manufacturer may have their own stated guidelines or recommendations. Though it is not possible to apply a hard and fast rule across the spectrum of users or applications, we can provide these basic guidelines:
- The HEPA filter should be visually inspected at every single bag change.
- With every other bag change the filter should be removed and the seal (including the filter and the area on which it mounts) should be inspected for debris that could compromise the seal. Carefully remove any debris with a light, clean, non-abrasive cloth with minimum pressure.
- NEVER use compressed air to 'clean' the filters as it may compromise the efficacy of the filter and the rated filtration.
- In case of any damage to the filter, replace it at once.
- Depending on the degree of use, a filter may need to be replaced every month or any other interval up to 6 months. Filters should be replaced every 6 months to maintain the rated performance.
- Avoid direct contact with the filter element (white cloth-like material).
- Replace filter immediately if it comes into contact with any sharp object or other harsh debris.
- One way to ensure the integrity of your CT Dust Extractor for use in RRP-related applications, as well as to help prevent cross-contamination of lead dust and debris would be to designate a CT Dust Extractor, dedicated solely for the purpose of working in lead-based paint applications. A secondary CT Dust Extractor could be designated for non-lead-based work.
- Replace filter immediately if used without a pre-filter or if the HEPA filter is left in place during a wet extraction operation.
- If you have any question or doubt as to the integrity of the HEPA filter, it is recommended that it is replaced at once.
Cheers,
Frank
