Help,
I am reviewing a 80-120 mil, seamless, fluid-applied urethane floor system with an impact resistance of 160 inch-pound force per cubic inch. I have no clue if 160 is good, bad or indifferent. I haven’t been unable to find a conversion to units I understand, such as psi or MPa.
Yes, I have a call into the manufacturer, but in the meantime I am reaching out to this discussion forum for help.
Thanks,
Wayne
Is there an ASTM associated with it?
Per cubic inch???
Yes. ASTM D4226 - Impact Resistance of PVC Building Products. Sounds like cherry picking a favorable ASTM. Two of use have read D4226 but cannot make the conversion.
According to Wikipedia, “inch-pound force per cubic inch” is a US unit used for measuring “toughness.” Perhaps its article on toughness could help:
Thanks Robert,
I have been to Dr Google and Dr. Wikipedia. I went to your source first but it did not answer my question. I’m so confused. LOL
Well as I said, it’s about toughness…
When the manufacturer gets back to you, ask them why they are using a PVC test for a polyurethane flooring system. They have tests for impact resistance for polyurethane coatings … ASTM D2794. At least that’s what I see from some resinous coating manufacturers. At a quick glance it looks like it fits better than PVC at least.
Sometimes I wish manufacturers would all play by the same rules.
Best way I know of to keep them honest is to not put them in the spec. When they ask why, tell them.
From what little I recall from college, PSI, PSF, MPa are measures of pressure. Inch-Pounds are typically a measure of energy or work. There are probably means to convert them online.
I don’t typically specify impact-resistance for flooring. Is this an industrial floor where workers are particularly accident-prone? Is it a Hollywood set where things are supposed to be crashing down on the floor? Is it perhaps a test laboratory where they use the floor as an impact surface? I’ve had clients come up with some pretty odd requirements (especially DoD projects) so I don’t reject any possible criteria that has to be met, I’m just always curious as to what drove us to solve problems such as this one.
BTW, if the concern is one of withstanding steel forklift wheels turning while fully loaded, I don’t think this is the right test or membrane.
Finding a comparative value from another material/manufacturer or a “conversion” of the tested inch-pound result from ASTM D4226 testing will probably be fruitless. This test has the hallmarks of a manufacturer’s unique in-house quality testing, which a marketing person chose to place in product literature.
ASTM’s introductory page (www.astm.org/Standards/D4226.htm)states that the “impactor head” is also important to the test result… try to find the same one from 2 manufacturers’ tests!
From ASTM D4226: “Choice of the specific impactor head configuration used is related to a variety of product attributes, such as specimen thickness and product toughness as well as abstract factors, such as the anticipated mode of failure in a specific application. The geometric uniqueness of the impactor head configurations prevents any comparison or correlation of testing results on samples tested with differing impactor head configurations. In general, the conical impactor, C.125, is useful to ensure failure of thicker specimens where the H.25 impactor caused no failure.”
I think Ken’s correct about not putting them in the spec unless there are other reasons to do so.
I am frequently frustrated by trying to compare resinous/seamless/fluid-applied flooring products. This is complicated by a lack of performance criteria from the Owner. Does it really need to have 10,000 psi compressive strength or will 3,000 psi do (is more really better or is it just more)? What kind of chemical resistance is really needed.
We occasionally require thermal resistance characteristics, and sometimes a higher compressive strength, but our designers will know that and choose an appropriate product. I then usually call Tom Dudick for assistance in finding comparables.
So, do we reject a product simply because we do not understand the relevance of a particular claimed attribute, don’t understand how it’s measured, don’t have exactly the same parallel data from other manufacturers, or just “don’t have a clue if it’s good, bad, or indifferent”? That seems pretty arbitrary…
Perhaps Colin can compile a list of Construction Consultants to the Industry (sorry Colin don’t want to lump more work on you), I believe NACE or SSPC may have a list of Coating Consultants, usually I reach out to the manufacturer for input, but to find an impartial consultant familiar with your region may be difficult.
“If there’s no way to compare performance with similar / comparable products, they are non-conforming”? Did I read that right? Isn’t “non-conformance” failure to meet the specified requirements? If no minimum criterion for “impact resistance” was specified, what ground is there to call it non-conforming?
Good one Robert.
Since the product proposed is a substitution I instructed the team to simply enforce the product substitution requirements/procedures in Div 01. The usual bull baffles brains ploy but in this case my team members a brain dead. They don’t know the requirements of our own specs. Happens all the time. They will blindly assume the risk.
For seamless flooring, I always have asked several manufacturers for recommendations on their systems to meet the heat, chemical, impact, traffic and movement characteristics given by the owner. There are so many formulations possible, that I have found this really is the best way.
I agree about the test criteria. Even if the criteria were intended for PVC, if all the manufacturers used it you could compare. Sounds like one of those areas where everyone does their own thing. There may not even be a test protocol for impact resistance of urethane flooring.