The direct answer is no.

A slip resistance result obtained from an existing pedestrian surface under AS 4663:2013 should not simply be converted into, or reported as, an AS 4586:2013 P rating.

Both Standards may involve wet pendulum testing, and the numerical result may appear similar to values associated with P classifications.

That does not make the outcomes interchangeable.

The applicable Standard, purpose of the test, condition of the surface and reporting framework all matter.

What is the fundamental difference between the Standards?

AS 4586:2013 concerns the slip resistance classification of new pedestrian surface materials.

AS 4663:2013 concerns the slip resistance measurement of existing pedestrian surfaces.

This creates a clear distinction:

• AS 4586:2013 asks: How should this new pedestrian surface material be classified under the applicable test method?
• AS 4663:2013 asks: What frictional characteristics does this existing installed surface demonstrate at the time and location tested?

One produces a classification of a new material.

The other measures an existing surface.

Why does the distinction matter?

An installed floor is not merely a laboratory sample in a larger format.

By the time a product is tested in situ, its performance may have been influenced by:

• installation and workmanship;
• adhesives, grout and joints;
• sealers and coatings;
• polishing or finishing;
• cleaning products and methods;
• wear from pedestrian traffic;
• trolleys, machinery or equipment;
• weather exposure;
• contamination;
• repairs or localised treatments;
• differences between production batches.

An original P classification can provide useful information about a new product.

It cannot guarantee that every installed area will continue to perform identically throughout its life.

Conversely, an in-situ result describes the area tested at that point in time.

It does not retrospectively reclassify the underlying product.

But do the numbers correspond to P ratings?

P classifications are connected to performance ranges obtained through the wet pendulum test method under AS 4586.

This can tempt people to take an AS 4663:2013 result, place it beside an AS 4586:2013 classification table and assign the apparently corresponding P rating.

The problem is not simply whether the numerical ranges look similar.

The problem is that the classification would be attributed under a Standard that was not used for the reported purpose.

A result should not be detached from its test method and reporting context.

If the report says that testing was conducted under AS 4663, the outcome should be reported and interpreted as an AS 4663:2013 result.

What should the AS 4663:2013 result be called?

The report should identify it as the slip resistance result or slip resistance value obtained for the existing surface under AS 4663:2013.

It may then be interpreted against an appropriate benchmark, requirement or source of guidance, provided that the basis for the comparison is clearly identified.

It should not be relabelled as an AS 4586:2013 P classification.

This preserves an accurate chain of evidence:

1. what was tested;
2. where it was tested;
3. which Standard was used;
4. what result was obtained;
5. what benchmark was applied;
6. what conclusion can reasonably be drawn.

Can the original product still have a P rating?

Yes.

A flooring product may have an AS 4586:2013 laboratory classification from testing performed on a new sample.

That P rating may be relevant to its initial specification or selection.

It should be supported by appropriate test documentation identifying the product, sample, test method and classification.

The installed floor can separately be tested under AS 4663:2013 to measure its present performance.

These are two different pieces of evidence:

• the AS 4586:2013 report describes the tested new material;
• the AS 4663:2013 report describes the tested existing surface.

They can be considered together, but one should not be substituted for the other.

What if a client specifically requests an in-situ P rating?

The request should be clarified before testing or reporting.

Often, the client is not deliberately asking for the wrong Standard.

They may simply use “P rating” as a general phrase for any wet pendulum result.

The testing provider should explain:

• which Standard applies to the surface;
• what kind of result can be reported;
• whether the surface is new material or an installed surface;
• what the client needs the evidence for;
• whether a numerical result, formal classification or risk-based interpretation is required.

Clarifying this at the beginning prevents a technically accurate report from being misunderstood later.

Why is an invented conversion risky?

Incorrectly presenting an AS 4663:2013 result as a P rating can create problems in:

• compliance documentation;
• product warranties;
• construction disputes;
• tender submissions;
• asset management;
• workplace safety reviews;
• expert evidence;
• incident investigations;
• insurance matters.

The issue is not that the numerical result becomes useless.

The issue is that its identity and evidentiary meaning have been changed.

A report should allow another competent person to understand what was done without reconstructing or guessing the testing process.

What is the correct approach?

For a new pedestrian surface material requiring classification, use the applicable AS 4586:2013 test method and report the classification permitted by that Standard.

For an existing installed pedestrian surface, test under AS 4663:2013 and report the numerical result for the location and conditions assessed.

Where interpretation is required, identify the source and reasoning used.

Do not disguise interpretation as a classification generated by a different Standard.

The practical rule

An AS 4663:2013 result may be compared or interpreted where appropriate, but it should not be converted into an AS 4586:2013 P rating.

The distinction protects the technical integrity of the report and helps the person relying on it understand exactly what the evidence shows.