What is a Standard?
Do you know your weight in pounds? How about in kilograms? Or in stones?? The need for standards may not be obvious until you realize that we use them every day.
When it comes to standards, measurement standards are probably the most familiar. The International System of Units (abbreviated SI from French: Le Système International d'Unités) is widely accepted in science and technology. The first metrology standards agreed on, the meter and the kilogram, were part of the 1875 Convention of the Meter, a diplomatic treaty between 54 nations. Today, the SI and other globally accepted standards are vital to continued progress in nanotechnology research and development, and for safe, secure, and responsible commercialization of nanotechnology in the years ahead.
However, nanotechnology depends on more than just measurement standards. In order to ensure consistency, repeatability, and accuracy there must be standards of practice (e.g., procedures and guidelines) and standards for verification (e.g., reference materials). In this way, we can categorize standards broadly into measurement standards, reference standards, and documentary standards.
Kinds of Standards
Measurement Standards
The International System of Units has seven base quantities: length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity. Their respective base units—the meter, kilogram, second, ampere, kelvin, mole, and candela—are often combined to make derived units such as the joule (energy, work, heat), hertz (frequency), and volt (electrical potential). All are relevant to nanotechnology, in particular, the unit of length at the nanoscale, the nanometer. This is a standard prefix unit that is derived from the base unit meter by subdividing the meter by a factor of one billion.
Standard prefixes for the SI units of measure | ||||||||||||
Multiples | Name | deca- | hecto- | kilo- | mega- | giga- | tera- | peta- | exa- | zetta- | yotta- | |
Prefix | da | h | k | M | G | T | P | E | Z | Y | ||
Factor | 100 | 101 | 102 | 103 | 106 | 109 | 1012 | 1015 | 1018 | 1021 | 1024 | |
Fractions | Name | deci- | centi- | milli- | micro- | nano- | pico- | femto- | atto- | zepto- | yocto- | |
Prefix | d | c | m | μ | n | p | f | a | z | y | ||
Factor | 100 | 10−1 | 10−2 | 10−3 | 10−6 | 10−9 | 10−12 | 10−15 | 10−18 | 10−21 | 10−24 |
A derived unit important to nanotechnology is the unit of force, the Newton. The force exerted by the cantilevers used in atomic force microscopes is typically specified in terms of nanoNewtons or one-billionth of a Newton. (For reference, a Newton is force about equal to the weight of an apple on Earth.)
Reference Standards
Standard reference materials are used to verify a quantitative measurement. These are materials that are certified by a national standards laboratory to have specified characteristics referenced to the fundamental SI system of physical units of measurement. The International Bureau of Weights and Measures (BIPM), located in Sèvres near Paris, France, has the task of ensuring world-wide uniformity of measurements and their traceability to the SI basic units.
Documentary Standards
Documentary standards define agreed-upon terminology or standard language for a field of science, engineering, or technology; they are agreed-upon means for conducting measurements; agreed-upon performance characteristics of instruments or commercial products; and particularly, they are documented agreements on means to facilitate trade and commerce.
Illustrative examples of documentary standards available for nanomaterials are listed in the table below. For a comprehensive list of nanotechnology-related standards, please visit each organization’s website.
Topic | Unique Identifier | Title |
Terminology | ASTM E2909-13 | Standard Guide for Investigation/Study/Assay Tab-Delimited Format for Nanotechnologies (ISA-TAB-Nano): Standard File Format for the Submission and Exchange of Data on Nanomaterials and Characterizations |
ISO/TS 80004-1:2010 | Nanotechnologies -- Vocabulary -- Part 1: Core terms | |
Measurement | ASTM E2490-09(2015) | Standard Guide for Measurement of Particle Size Distribution of Nanomaterials in Suspension by Photon Correlation Spectroscopy (PCS) |
ISO/TR 13014:2012 | Nanotechnologies -- Guidance on physico-chemical characterization of engineered nanoscale materials for toxicologic assessment | |
EHS Effects | ASTM E2524-08(2013) | Standard Test Method for Analysis of Hemolytic Properties of Nanoparticles |
ISO/TS 12901-1:2012 | Nanotechnologies -- Occupational risk management applied to engineered nanomaterials -- Part 1: Principles and approaches | |
Education | ASTM E2996-15 | Standard Guide for Workforce Education in Nanotechnology Health and Safety |
Who Sets Standards?
Around the world, there are numerous standards-setting groups that are involved in developing nanotechnology standards. Some of the leading standards setting organizations and their relevant nanotechnology committees are (in no particular order):
- International Standardization Organization (ISO) Technical Committee (TC) 229 on Nanotechnologies
- ASTM International Committee E56 (Nanotechnology) (formerly known as the American Society for Testing and Materials)
- International Electrotechnical Commission Technical Committee 113 (Nanotechnology for electrotechnical products and systems)
- Institute of Electrical and Electronics Engineers’ Nanotechnology Council
These groups develop voluntary standards. Standards that are the best formulated, with the strongest basis in science, are most likely to be adopted by the global community. U.S. leadership and participation in the international standards-setting process allows the United States to help shape the strategic and technical direction of nanotechnology development everywhere. Additionally, other groups are involved in coordinating the development of standards, such as the American National Standards Institute (ANSI), which hosts a Nanotechnology Standards Database and accredits organizations involved in standards.
U.S. Federal Government research related to measurement within science and technology is led by the National Institute of Standards and Technology (NIST). NIST representatives lead ASTM International’s Committee E56 on Nanotechnology. A U.S. Technical Advisory Group (TAG) (accredited by ANSI) represents the United States at ISO TC 229, Nanotechnologies. The TAG is responsible for formulating positions and proposals on behalf of the United States with regard to ISO standardization activities related to nanotechnology. The U.S. also holds leadership of ISO TC 229’s Working Group 3: Health, Safety and Environmental Aspects of Nanotechnologies, with a representative from The National Institute for Occupational Safety and Health (NIOSH).
Where can I get more information?
General information on standards of all kinds can be found at Standards.gov.
The Interagency Committee on Standards Policy, also known as the ICSP, provides advice and recommendations to the Secretary of Commerce and other Executive Branch agencies on matters related to standards policy. This committee has Standards Executives from each cabinet level Department and several independent Federal Agencies and Commissions. To find the Standards Executive from a given U.S. agency, please see the ICSP Members Directory.
The ANSI Nanotechnology Standards Panel has recently started the ANSI-NSP Newsletter with the objective of getting information out about standards related developments.