WHAT IS A DIMENSION STONE
Dimension Stone is a collective name used for various natural stones that have been quarried and trimmed to speciﬁc sizes or shapes for structural or decorative purposes in construction or monumental applications. The basic categories of dimension stones are: Marble, Granite, Limestone, Travertine, Slate and Sandstone.
THE DIMENSION STONE INDUSTRY
The Dimension Stone Industry is valued at over US$60 billion worldwide. The major producers of raw natural stone are China, India, Italy, Iran, Turkey, Brazil, Egypt, Portugal, USA, Greece, France and South Africa. The major consumers of ﬁnished products are China, USA, India, Italy, Spain, South Korea, Germany, France, Japan, Taiwan, Brazil, UK, Nigeria. The major exporters of raw stone are India, Turkey, Italy, Greece, Spain, Brazil, China, Egypt, and South Africa.
WHY INTERNATIONAL STANDARDS ARE IMPORTANT
In today’s building environment, the emphasis is on safe, permanent, low maintenance products, of which stone leads the list in the minds of architects, designers, and consumers worldwide.
Without a consistent, realistic set of standards and testing procedures for stone products, the stone industry as a whole would be in disarray. The standards that have been developed and set in place for these products are important tools to help protect end users, individual companies, and the industry from negative effects related to product failures. Materials standards help to prevent the use of stone products for unsuitable applications.
Marble Institute of America has Produced and Published A Natural Stone Institute survey titled:
‘Standards and Specifications for Stone Products, An excerpt from the Dimension Stone Design Manual, Version VIII (May 2016)’
ASTM – AMERICAN SOCIETY FOR TESTING AND MATERIALS
ASTM International, originally known as the American Society for Testing and Materials (ASTM), was formed in 1898.
ASTM International is a globally recognized leader in the development and delivery of voluntary consensus standards. Today, over 12,000 ASTM standards are used around the world to improve product quality, enhance health and safety, strengthen market access and trade, and build consumer confidence.
Standards developed at ASTM are the work of over 30,000 ASTM members. These technical experts represent producers, users, consumers, government and academia, representing 140 countries. Working in an open and transparent process and using ASTM’s advanced IT infrastructure, our members create the test methods, specifications, classifications, guides and practices that support industries and governments worldwide.
ASTM continues to play a leadership role in addressing the standardization needs of the global marketplace. Known for its best in class practices for standards development and delivery, ASTM is at the forefront in the use of innovative technology to help its members do standards development work, while also increasing the accessibility of ASTM International standards to the world.
In recent years, stakeholders involved in issues ranging from safety in recreational aviation, to fiber optic cable installations in underground utilities, to homeland security, have come together under ASTM to set consensus standards for their industries.
1 Material Specifications
1.1 ASTM C503, Standard Specification for Marble Dimension Stone (Exterior)
1.2 ASTM C568, Standard Specification for Limestone Dimension Stone
1.3 ASTM C615, Standard Specification for Granite Dimension Stone
1.4 ASTM C616, Standard Specification for Quartz-Based Dimension Stone
1.5 ASTM C629, Standard Specification for Slate Dimension Stone
1.6 ASTM C1526, Standard Specification for Serpentine Dimension Stone
1.7 ASTM C1527, Standard Specification for Travertine Dimension Stone
The TEAM (TEAM=TEsting and Assessment of Marble and limestone) project
The use of natural stone as facade cladding has been shown to have much lower life cycle costs and they are more environmentally friendly than comparable products of concrete, glass, and steel. Promoting the use of natural stone has therefore a great positive impact on the environment. However, the number of occurrences of bowing and expansion of marble and limestone panels has led to increased maintenance costs, significant safety risk, and negative publicity. The lack of knowledge of a solution to the problem of bowing marble has a large negative effect on the entire stone trade. In response, short-sighted and less durable construction solutions are used as an alternative, adding to the decreasing export figures and numbers of employees within the stone sector. The TEAM (TEAM=TEsting and Assessment of Marble and limestone) project addresses a problem with marble types, from several European countries, that display bowing on facades in both cold and warm climates. There is, therefore a need to develop harmonized European standards for differentiating between marble that is susceptible to bowing and marble that is not. Resolution No. 013, in May 1999 taken by the European Committee for Standardization (CEN), Technical Committee (TC) 246 Natural Stone states the urgent needs “to develop a direct test method of the bowing risk for marble cladding products.”
Research both in the laboratory and the field were performed on a large number of different stone types from different countries and used in different climates. This gave the explanation of degradation mechanisms and led to the determination of the critical influencing factors. Two tests methods, including precision statements: one for bowing and one for thermal and moisture irreversible expansion have been prepared for submission to CEN TC 246. Repair techniques based on the use of surface coating and impregnation systems has been tested at laboratory and in the field. Positive side effects including increased durability and easier cleaning have been observed. Guidelines for production and product control have been proposed, and an instruction for stone sampling and description has been developed.
ANSI –AMERICAN NATIONAL STANDARDS INSTITUTE
The American National Standards Institute (ANSI), founded in 1918 by five engineering societies and three government agencies, is a private, not-for-profit organization that administers and coordinates U.S. voluntary standards and conformity assessment acti-vities. The Institute represents the interests of its nearly 1,000 company, organization, government agency, institutional, and international members through its office in New York City, and its headquarters in Washington, D.C.
ANSI Specifications and Standards
ANSI currently provides a forum for over 270 ANSI-accredited standards developers representing approximately 200 distinct organizations in the private and public sectors. These groups work cooperatively to develop voluntary national consensus standards and American National Standards (ANS).
The ANSI standardization process provides and promotes standards that withstand scrutiny, yet protect the rights and interests of all participants. This process helps quicken the market acceptance of products, while advising how to improve the safety of those products to protect consumers.
U.S. standards are promoted internationally by ANSI. The organization also advocates U.S. policy and technical positions in international and regional standards organizations, as well as supporting the acceptance of international standards as U.S. standards where they meet the needs of the user community.
The Institute is active internationally with the International Organization for Standardization (ISO), and, via the U.S. National Committee (USNC), the International Electrotechnical Commission (IEC). In many instances, U.S. standards are taken forward to ISO and IEC through ANSI or the USNC, where they are adopted in whole or in part as international standards.
NSF International, formerly the National Sanitation Foundation, is a not-for-profit, non-governmental organization that provides standards, certification, education, and risk management services in the fields of public health safety and the environment. NSF was founded in 1944 in response to a need for a single set of food equipment sanitation standards that manufacturers and operators could accept and regulators could adopt into code. NSF has 21 standards for all types of products and materials used in food service. The standards contain requirements for materials, design, construction, and performance of food service equipment to ensure that it is safe and can be kept sanitary. Today, NSF Food Equipment Standards are globally recognized, and certification to the standards is required by regulators, specified by end users, and marketed by manufacturers.
1. NSF/ANSI Standard 51, Food Equipment Materials
CEN – EUROPEAN COMMISSION FOR STANDARDIZATION
1. CEN Specifications and Standards
CEN specifications and standards are in the process of being compiled. This information will be available at a later date.
All standards and specifications are revised or updated periodically. The current status of any standard or specification can be confirmed by contacting the proper authority.
2. European Standardization Organizations
The three European Standardization Organizations, CEN, CENELEC and ETSI are officially recognized as competent in the area of voluntary technical standardization. The European Union (EU) Regulation (1025/2012) which settles the legal framework for standardization, has been adopted by the European Parliament and by the Council of the EU, and entered into force on 1 January 2013.
3. Cooperation of the European Standardization Organizations: Joint Presidents’ Group
The three European Standardization Organizations cooperate on policy and technical matters of common interest. This cooperation is coordinated by the Joint Presidents’ Group (JPG). As its name implies, JPG comprises the Presidents and Vice-Presidents of CEN and CENELEC and their ETSI equivalents (General Assembly Chair and Vice-Chairs, and ETSI Board Chair), together with the Director General of CEN and CENELEC and the Director General of ETSI.
The JPG enables discussion of matters of common interest to the three European Standardization Organizations (ESOs). As the highest policy-making body in European standardization, it takes due account of political and economic developments likely to affect standards-making. It agrees a common approach to technical issues of interest to all three bodies, and towards standards organizations in other regions of the world, by arranging collaboration meetings and concluding formal agreements (as appropriate).
ASTM / CEN COMPATIBILITY
In general, the test procedures published by ASTM test stone to evaluate the same properties determined by the test procedures authored by CEN. Despite this, there exists no correlation between the values obtained in certain ASTM procedures and their CEN counterparts. Abrasion resistance and friction are two examples where the test methods differ so greatly that one cannot make a reasonable correlation between the results of the two procedures. Therefore, having data obtained from one system doesn’t allow one to make even a rough estimate of what the results would have been if tested in the other system.
There are five properties, however, where the test methods are similar: Absorption, Density, Compressive Strength, Modulus of Rupture, and Flexural Strength.
The procedures to test absorption, ASTM C97, and its counterpart, EN 13755 Determination of Water Absorption at Atmospheric Pressure, use a similar sized specimen with a similar procedure. The primary difference is the mode of immersion, in which case the ASTM method immerses the test specimen completely without delay. The EN procedure immerses the specimen to only ½ of its depth for the first hour, then to ¾ of its depth for the second hour, and completely immersed for the remainder of the time. The rationale behind this protocol is that a cubic shaped stone sample, if immediately submerged, can trap the equivalent of an air bubble in its interior fabric and never achieve full saturation. By stepped immersion, this air is more efficiently evacuated from the sample.
Density is also tested by ASTM C97, but in EN procedures it is tested by EN 1936 Method of Real and Apparent Density, and of Total and Open Porosity. While the EN procedure includes additional sub procedures testing varying properties, the Apparent Density value is tested similarly to how density is determined in the ASTM system.
ASTM C170 or EN 1926 Determination of Uniaxial Compressive Strength are very similar procedures using similar specimen sizes for the purpose of determining compressive strength.
Modulus of Rupture
Modulus of Rupture per ASTM C99 can be compared to EN 12372 Determination of Flexural Strength under Concentrated Load. The latter includes more latitude in the finishes of the provided sample and uses a deeper and longer specimen. More significantly, the EN procedure calls for a span-to-depth ratio of 5:1, while the ratio in the ASTM procedure is slightly over 3:1. This would predictably skew the results; however the two procedures would be expected to have at least some level of correlation. It should be noted that neither procedure would be the preferred method for determining bending strength.
The ASTM C880 Flexural Strength procedure is similar to the EN 13161 Determination of Flexural Strength under Constant Moment procedure. The most significant difference is the span to thickness ratio, which is 10:1 in the ASTM procedure versus 5:1 in the EN method. The second significant difference is that the loading rollers are at 1/4 and at 1/3 of the span in the ASTM and EN methods, respectively. Both of these variations would be expected to produce slightly higher values in the EN method.
The ASTM C1721 and EN 12407 methods
Not a test method, but rather an analysis, the ASTM C1721 and EN 12407 methods for petrographic analysis of dimension stone are similar. Either of these is likely to be significantly modified by the user to tailor them to the specific stone type. While the above suggests that there is good correlation in these particular tests, such correlative data is likely only usable for preliminary study and evaluation. Final engineering and specification compliance will normally require data obtained from the exact, specified test procedure.
Currently, there are over twenty five documents published by ASTM International related to dimension stone. Documents pertaining to dimension stone fall into four different categories of ASTM publications:
A Terminology, or nomenclature, standard is a glossary of industry or material specific terms. It includes definitions of terms that are either unique to the industry/product, or are used in that industry differently than their common usage.
Guides are simply a collection of information about a subject. They suggest no specific or prescribed course of action.
A Specification standard merely defines the measureable requirements that a product must meet to satisfy that standard.
A Standard Test Method, just as the name implies, is a documented protocol by which a material is to be tested to quantify a specific property. The test methods will include information on the physical test specimen size, shape, and surface treatments, as well as recommendations of sample population.
BSI is a non-profit distributing organization and offers global services in the linked fields of standardization, systems assessment, product certification, training and advisory services.
The British Standards Institution (BSI) was established in 1901 as the Engineering Standards Committee. A Royal Charter was granted in 1929, with the organization’s aims and objectives including:
GULF COOPERATION COUNCIL STANDARDIZATION ORGANIZATION
Standard Specification for Marble Dimension Stone
GSO ASTM C503 / C503M:2015
Adopted Standard : ASTM C503 / C503M:2010 , Related Documents : Updates GSO ASTM C 503:2008
ICS : 91.100.15 – Mineral materials and products , Including earth, sands, clay, slates, stones, etc.
This specification covers the material characteristics, physical requirements, and sampling method appropriate to the selection of marble dimension stone for general building and structural purposes. Dimension marble shall include stone that is sawed, cut, split, or otherwise finished or shaped into blocks, slabs or tiles, and shall specifically exclude molded, cast and artificially aggregated units composed of fragments, and also crushed and broken stone. Marbles covered here are classified as either calcite or dolomite. The physical property requirements to which marble stones shall adhere to are absorption by weight, density, compressive strength, modulus of rupture, abrasion resistance, and flexural strength. This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.
DATA RECEIVED FROM:
Marble Institute of America: ‘Standards and Specifications for Stone Products, An excerpt from the Dimension Stone Design Manual, Version VIII (May 2016) ’
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