Testing NBC filters for collective protection use
NBC filters for collective protection purposes are the most critical component in the ventilation system of protective structures, and as such must meet very strict requirements:
- Aerosol and gas separation efficiencies
- Shock-pressure resistance
- Density and compression strength (in lead-sealed storage unit)
- Long-time stability (materials, protection against corrosion)
- Mass and pressure drop (exchangeability)
All equipment used by the Swiss Protection & Support system must comply with the Statement of Requirements of the Federal Office for Civil Protection TPH-06.
In addition to testing separation efficiency, quality controls are also performed on the construction and manufacture of these NBC filters.
On safety and cost grounds, tests on the separation efficiency of NBC filters can only be performed in a laboratory setting. For this reason an appropriate substitute is used to test whether full sorption efficiency, i.e. the same adsorption capacity as in a comparative laboratory sample, is achieved through the error-free construction of the filter bed and the assembly of the sorption medium (activated carbon).
This indirect testing method enables the laboratory to carry out quality controls on larger NBC protective filters at relatively little cost. Where the filter must be tested exclusively on a scale of 1:1 with army-relevant substances, our experience shows that quality controls tend to be neglected somewhat. It should also be noted that any so-called "non-destructive" test involving only a short pulse, does not provide the same results.
Standard testing procedures within the scope of accreditation of Testing Laboratory STS 055
| Aerosol permeability tests on HEPA filter materials and components, including gas filters | SOP L 055 202 |
| Testing the emergency water and dry toilet equipment of the Protection & Support service | SOP L 055 206 |
| Testing the bond strength of surface protection, sealing compounds and adhesives | SOP L 055 207 |
| Testing the dynamic sorption of gas filters | SOP L 055 208 |
| Testing the density of hose sealing joints in ventilation equipment | SOP L 055 218 |
| Testing HEPA filter media | SOP L 055 220 |
| Testing of gas filters | SOP L 055 221 |
| Testing dust protection material for use in gas filters | SOP L 055 223 |
| Aerosol permeability of HEPA filter materials and components, including gas filters | SOP L 055 201 |