Why there is no single "particle value"
One of the first questions from purchasing or quality teams is usually: "How many particles does this mop release?" The question is right, but a single-number answer is incomplete. The amount of particles a mop or wipe releases depends on its construction, on whether it is used dry or wet, on the movement applied and on which size range is counted. That is why OWMO publishes a particle result together with the configuration measured and the test conditions, not against a product name alone.
This article summarises what to check when you read a particle result and which questions the result does not answer.
Particle release and linting are separate questions
Two different risks in a controlled area are often grouped under one heading:
Particle release: the particles a product generates in dry or wet use. In dry methods the product is subjected to a defined mechanical movement and the particles released into the air are counted; in liquid methods the particles the product releases into a liquid are counted. OWMO's test matrix names the Helmke drum, liquid particle counting or another relevant method as examples.
Linting: fibre or filament residue left on the wiped surface. It is assessed with methods such as lint testing and microscopy, separately under dry, wet and abrasion conditions.
In addition, non-volatile residue (NVR) transferred to the surface and ionic residue are treated as separate measurements, especially in sensitive processes such as electronics and optics. A good result in one does not replace another.
The conditions that shape the result
The OWMO mop architecture covers 2, 3, 4 and 5 layer constructions; size and grammage can vary with the task. A particle or lint result cannot be inferred from layer count alone. A meaningful result comes with at least:
layer count, grammage, size, material and edge/attachment construction,
dry or wet condition and, if wet, the liquid or chemical used,
the movement applied and the test duration,
the particle size range counted and the result unit (count per size range).
A different layer or grammage combination within the same product family needs its own report.
Dry and wet results cannot be converted into each other either. If you will use the product on site wetted with IPA or a disinfectant, a result obtained in dry condition may not represent your task. With reusable products, performance can change after a wash or autoclave cycle; post-cycle particle and lint results are therefore assessed separately from those of a new product.
What to look for on a test card
In OWMO's evidence approach every test card should carry the same fields:
Identity: report number, testing body, date and validity.
Sample: SKU, material, layers, grammage, size and, where applicable, the sterilisation method.
Method: standard or validated method, equipment, liquid/chemical, environment and conditions.
Result: numerical value, unit, limit and pass/fail decision.
Scope: the use scenario it applies to and any excluded SKUs.
Version: revision, change control and revalidation date.
If any of these fields is missing, treat the result as preliminary information rather than as evidence that applies to your task.
What a result does not tell you
It does not mean "zero particles". Every textile and every movement can generate measurable particles. The accurate statement is the particle count and size range measured with a specific method.
It does not guarantee the room's class. ISO 14644-1 classifies the air cleanliness of the environment. Using a product with a low particle result in an ISO Class 7 or 8 room does not maintain the room's class; room performance is managed together with HVAC, personnel, process, cleaning SOPs and the monitoring plan.
It does not mean the product is sterile. Sterile status is shown by a validated sterilisation process and a sterile barrier package; a particle result does not answer that question.
A fabric report does not cover the finished product. A report on NEWSOUL or FRIGG fabric does not automatically prove the performance of a finished OWMO mop or wipe. If material, grammage, layers, attachment, edge, sterilisation and packaging are not within the same scope, an additional product test is required.
Preparing for a technical consultation
To answer the particle question properly, a good starting point is to share in your request: the environment (ISO class, hospital clean area, laboratory or controlled production), the surface to be wiped, dry or wet use, the chemical used, the particle size range that is critical to you and any additional needs such as lint, NVR or ionic residue.
Configuration-specific particle and lint results for OWMO products are confirmed per product at the sample and quotation stage. You can review the evidence structure on the Evidence Lab page and share your requirements through the technical consultation form.
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