Certification of the Diffuser for ASTM D892 and D6082 Foam Testing
The diffusers used in foam testing must meet a certain permeability and pore diameter. The diffusers, especially the ceramic stones, change over time and fall out of specification, sometimes very quickly. They should be verified at least every week or every ten tests. The frequency necessary can only be determined by individual laboratory based on its experience for the types of samples analyzed.
Manual and Automated Diffuser Certification Apparatus are available from Lawler to save time and keep track of how the diffuser is changing.
Lawler has built an automated certification unit and dedicated it for re-certification of diffusers. For a small fee labs can send their diffusers to Lawler and get them back with results.