Are All Are All Numbers Numbers Equal?Equal?

54 54 4343

6666 9999

7878

47 47 95953232 8181

12129898

786786

Are All Numbers Equal?Are All Numbers Equal?

Of course not. Some are higher, lower, Of course not. Some are higher, lower, bigger smaller than others.bigger smaller than others.

But that is all. They do not have any But that is all. They do not have any meaning unless you references as to meaning unless you references as to what they represent.what they represent.

They are just numbers!They are just numbers!

In order to give them a relative value In order to give them a relative value and compare them, they need to be and compare them, they need to be given with the same point of reference.given with the same point of reference.

ExamplesExamples A Canadian asks an American: How fast A Canadian asks an American: How fast

can you drive on the Interstates? 70 is can you drive on the Interstates? 70 is the reply.the reply.

How fast can you drive on the highways How fast can you drive on the highways in Canada? 100 says the Canadian.in Canada? 100 says the Canadian.

The answers are confusing and may be The answers are confusing and may be interpreted wrong unless you add 70 interpreted wrong unless you add 70 m/hm/h & 100 & 100 k/hk/h. . In fact the American In fact the American can drive faster!!can drive faster!!

The rest of the answer is in the detailsThe rest of the answer is in the details

Another ExampleAnother Example

The Texan asks the Canadian from Ontario:The Texan asks the Canadian from Ontario:

What’s the temperature today? 28 is the reply.What’s the temperature today? 28 is the reply.

Hey – you should be here in Dallas, it’s 79.Hey – you should be here in Dallas, it’s 79.

The truth is that it is warmer in Toronto at 28 The truth is that it is warmer in Toronto at 28 CC

than in Dallas at 79 F.than in Dallas at 79 F.

Voila! “The rest of the story is in the details”Voila! “The rest of the story is in the details”

STCSTC And so it is with STC.And so it is with STC. STC 53, STC 44, STC 50 – “STC STC 53, STC 44, STC 50 – “STC

anything” is meaningless until you anything” is meaningless until you further define what the number further define what the number represents and when & how it was represents and when & how it was achieved.achieved.

When discussing Moderco STC values When discussing Moderco STC values you have to explain the number and why you have to explain the number and why it is important for the spec writer to it is important for the spec writer to understand the entire STC testing understand the entire STC testing process. process.

AcousticsAcoustics

The acoustic qualities of an operable wall The acoustic qualities of an operable wall are the most disregarded and casually are the most disregarded and casually treated feature at the specifying and treated feature at the specifying and purchasing stages of a project but become purchasing stages of a project but become the biggest concerns if expectations are the biggest concerns if expectations are not realized after installation. not realized after installation.

More time & effort is spent on hinges More time & effort is spent on hinges colors & sizes and gauges of frames when colors & sizes and gauges of frames when writing specifications than proof of writing specifications than proof of acoustic quality. acoustic quality.

Typical Acoustic Typical Acoustic SpecificationSpecification

The operable partition shall have The operable partition shall have been tested in an independent been tested in an independent acoustical laboratory in accordance acoustical laboratory in accordance with ASTM E-90 to attain no less with ASTM E-90 to attain no less than the STC rating specified.than the STC rating specified.

And someplace else it will say: STC And someplace else it will say: STC 50 or whatever50 or whatever

Few details. Very loose & open. Few details. Very loose & open. Open to all kind of interpretations.Open to all kind of interpretations.

What Should the What Should the Specification say? Specification say?

““Independent Acoustical Laboratory”.Independent Acoustical Laboratory”. This should be clarified as an “This should be clarified as an “NIST/NVLAP NIST/NVLAP accredited,accredited, currently operating laboratory, currently operating laboratory, available to verify test results.”available to verify test results.”

NIST: A non regulatory federal agency NIST: A non regulatory federal agency within the US Department of Commerce. within the US Department of Commerce. Web site: Web site: www.nist.gov/index.htmlwww.nist.gov/index.html

NVLAP: A division within NIST. Stands for NVLAP: A division within NIST. Stands for National Voluntary Laboratory National Voluntary Laboratory Accreditation Program. Web site: Accreditation Program. Web site: www.nist.gov/ts/ssd/nvlap/index.cfmwww.nist.gov/ts/ssd/nvlap/index.cfm

An NVLAP laboratory ensures competence, An NVLAP laboratory ensures competence, continuity & equality.continuity & equality.

What about What about “Independent?”“Independent?”

Suppose the laboratory is NIST/NVLAP Suppose the laboratory is NIST/NVLAP accredited. What about “independent” accredited. What about “independent” from the manufacturer doing the from the manufacturer doing the testing?testing?

The interpretation of sound test results The interpretation of sound test results is an inexact science leaving much to the is an inexact science leaving much to the discretion of the technician.discretion of the technician.

In order to ensure equality & fairness In order to ensure equality & fairness the Laboratory should not be owned by the Laboratory should not be owned by the manufacturer. It should be the manufacturer. It should be “independent”.“independent”.

ASTM InternationalASTM International

http://www.astm.org/index.shtmlhttp://www.astm.org/index.shtml Formerly known as American Formerly known as American

Society for testing and Materials.Society for testing and Materials. Develops and encourages Develops and encourages

standardization for world’s market standardization for world’s market place.place.

World recognition and acceptance.World recognition and acceptance.

ASTM E-90ASTM E-90

ASTM E-90: Standard Test Method for ASTM E-90: Standard Test Method for Laboratory Measurement of Airborne Laboratory Measurement of Airborne Sound Transmission Loss of Building Sound Transmission Loss of Building Partitions and Elements.Partitions and Elements.

Original ASTM E-90 test standards was issued Original ASTM E-90 test standards was issued in 1955.in 1955.

Since then there have been many revisions Since then there have been many revisions (maximum 5 years span) indicated by a suffix of (maximum 5 years span) indicated by a suffix of the year: E-90-the year: E-90-0909..

E-90-09 (2009) is the most recent revised E-90 E-90-09 (2009) is the most recent revised E-90 procedure.procedure.

Equality of ASTM E-90 Equality of ASTM E-90 TestsTests

Unofficially, ASTM has concluded that E-90 Unofficially, ASTM has concluded that E-90 tests are considered equal based on an tests are considered equal based on an upward progression of a maximum of 4 tests.upward progression of a maximum of 4 tests.

According to this fact, the only E-90 tests According to this fact, the only E-90 tests that should be considered as valid today are that should be considered as valid today are E-90-E-90-9999, , 0202, , 0404 & & 0909..

Tests conducted prior to E-90-99 should be Tests conducted prior to E-90-99 should be viewed as suspect.viewed as suspect.

We have seen tests identified as E-90-70 We have seen tests identified as E-90-70 being submitted as proof.being submitted as proof.

One manufacturer regularly submits E-90-One manufacturer regularly submits E-90-83.83.

The same manufacturer has not completed The same manufacturer has not completed any STC testing since 1990.any STC testing since 1990.

Conclusion &What to do?Conclusion &What to do?

Talk to your spec writers about more Talk to your spec writers about more than an STC number. Just considering than an STC number. Just considering the number as proof of acoustic validity the number as proof of acoustic validity is misleading.is misleading.

Get them to include an oldest acccepted Get them to include an oldest acccepted version of E-90 in their specification.version of E-90 in their specification.

Not all numbers are equal.Not all numbers are equal. Talk about NVLAP accredited Talk about NVLAP accredited

“Independent” laboratories.“Independent” laboratories.

This is the SpecificationThis is the Specification

The partitions shall have been tested in The partitions shall have been tested in a NIST/NVLAP independent (not owned a NIST/NVLAP independent (not owned or operated by the manufacturer) or operated by the manufacturer) accredited, currently operating accredited, currently operating laboratory, available to verify test laboratory, available to verify test results, in accordance with ASTM E-90 results, in accordance with ASTM E-90 sound test procedure. Sound tests sound test procedure. Sound tests conducted prior to 1999 (E-90-99) will conducted prior to 1999 (E-90-99) will not be considered as proof. Products not be considered as proof. Products tested prior to 1999 are not acceptable.tested prior to 1999 are not acceptable.

How do we Sell 54 & 55?How do we Sell 54 & 55?

#1#1 – Educate your designers in that there is – Educate your designers in that there is more to STC than simply a number. Tell them more to STC than simply a number. Tell them the rest of the story. The submission of a the rest of the story. The submission of a “number” is not a proof.“number” is not a proof.

#2#2 – Custom write a specification including – Custom write a specification including the paragraph that details acoustic STC the paragraph that details acoustic STC standard.standard.

#3 #3 –– ModercoModerco will guarantee a NIC 42 on will guarantee a NIC 42 on both the STC 54 & 55. You must discuss with both the STC 54 & 55. You must discuss with us prior to bidding. We recommend that all us prior to bidding. We recommend that all projects requiring a NIC 42 be priced by projects requiring a NIC 42 be priced by Moderco.Moderco.

How do we Sell 54 & 55.How do we Sell 54 & 55.

#4#4 – Bid Smart. If a STC 53 is specified – bid a – Bid Smart. If a STC 53 is specified – bid a STC 54 700 Series. We should be very STC 54 700 Series. We should be very competitive. Do not bid a STC 53 Signature.competitive. Do not bid a STC 53 Signature.

#5#5 – Bid Smart. If a STC 55 is specified, bid a – Bid Smart. If a STC 55 is specified, bid a Signature STC 55 with an alternate for an STC Signature STC 55 with an alternate for an STC 54 700 Series.54 700 Series.

#6#6 – When you can, always bid an alternate – When you can, always bid an alternate for a STC 54 700 Series. We will be very for a STC 54 700 Series. We will be very competitive.competitive.

#7#7 – Read Sales-Bulletin #10-01 and the ±1 – Read Sales-Bulletin #10-01 and the ±1 factor.factor.

#8#8 – Custom write a specification saying “STC – Custom write a specification saying “STC less than 54 is not acceptable.”less than 54 is not acceptable.”

Any Questions?Any Questions?

Keep in mind, we have a huge edge Keep in mind, we have a huge edge over our competitors when it relates over our competitors when it relates

to sound tests, let’s use it to our to sound tests, let’s use it to our benefit. benefit.