How we identify synonyms of Chemical and Material names
When you look up a Chemical or Material in DCRG, Ratings are provided from chemical resistance tables for that name, as well as for synonyms of that substance. DCRG has processed and resolved synonyms so you don't need to know synonyms to find the relevant data in different chemical resistance tables.
When there is doubt, we don't make assumptions.
Many Names for the Same Thing
For both Materials and Chemicals you'll find multiple names that refer to the same substance.
- Hydrochloric Acid
- Muriatic Acid
- HCl
- all refer to the same strong acid
- MEK
- Butanone
- methyethyl ketone
- Methyl Ethyl Ketone
- are all terms for the popular solvent
- Alums, K
- Potash Alum
- Potassium Aluminum Sulfate
- a well known chemical with many other names
- 316 Stainless Steel
- Stainless 316
- 316 SS
- are all terms for the common molybdenum-alloyed steel
- FKM_A
- Viton A
- a family fluorocarbon-based fluoroelastomer commonly found in O-rings
- Nitrile
- NBR
- Buna N
- Acrylonitrile
- all refer to the same the oil-resistant synthetic rubber
This is a fact of the industry, but to provide streamlined, organized data we need to simplify search results and the final reports that we deliver.
How DCRG Simplifies Naming
In DCRG reports, we identify chemicals and materials consistently by a single name, what we call a Primary Name. Regardless of how the data was identified in the source documents, we use the Primary Name. — the original documents are cited for your reference.
Occasionally, it's necessary to show a common name alongside our of Primary Name. In this case, the Primary Name will be shown in italics (even if they are the same).
- 316 Stainless Steel
- Stainless 316
- always shows as 316 SS
- FKM_A
- always shows as Viton A
- Nitrile
- NBR
- Acrylonitrile
- always shows as Buna N
- Muriatic Acid
- HCl
- always shows as Hydrochloric Acid
- MEK
- Butanone
- methyethyl ketone
- always shows as Methyl Ethyl Ketone
- Alums, K
- Potash Alum
- Potassium Aluminum Sulfate
- always shows as Potassium Alum
The remainder of this article describes how we define these synonyms.
When are Names the Same?
TODO: Elaborate a bit
- Alternate names, like Buna-N, NBR, and Nitrile Acrylonitrile which all refer to the material that we call Buna N.
- Verbose names, like Low-density polyethylene which refers to LDPE.
- Abbreviations, like IIR which refers to Butyl
The Same Name, Slightly Changed
This is very common and the easiest to handle. It's also a significant part of what makes searching by hand error-prone and time-consuming.
316 Stainless Steel or 316SS or Stainless steel 316
Different Names, but the Same Substance
Completely different names that refer to the same substance
FFKM and Chemraz
methyl ethyl ketone, MEK, and butanone identify the same chemical that DCRG will consistently refer to this chemical as Methyl Ethyl Ketone;
- different names for the same chemical are common (example: FFKM and Chemraz both identify perfluoroelastomers, but DCRG distinguishes between the two)
- the substance can be presented in one of different ways (example: Alcohol, ethyl or Ethyl alcohol or ethanol; 316 Stainless Steel or 316SS or Stainless steel 316)
Using Existing Standards and Practices
There are a range of well-established organizations, standards, and practices that address different categories of substances.
For chemicals, we define a synonym conservatively, using four nationally - and internationally recognized registries of chemical information:
- ChemIDplus Advanced - U.S. National Institutes of Health (NIH)/National Library of Medicine
- Common Chemistry - Chemical Abstracts Service, a division of the American Chemical Society
- PubChem Compound - NIH/National Institute of Biotechnology Information
- NIST Chemistry WebBook - U.S. National Institute of Standards and Technology (NIST)
For each Chemical Name:
- we search these registries to find a CAS Registry Number(s) (CAS RN) associated with the exact match to the name.
- If we find an exact match in any registry, that Chemical name is tagged with the CAS RN. Occasionally we find a name associated with multiple RNs.
- Many names don't appear in any registry. This could be because they are products, a mix of many components; tradenames; or misspellings.
With this:
- Chemical names with the same CAS RN are considered synonyms, as a
CAS RN is defined in the CAS Registry,
the world's most comprehensive and high-quality compendium of publicly disclosed chemical information.
This provides a documented method for defining synonyms. - If the name appears linked to more than one CAS RN, DCRG considers it a distinct Chemical from any name associated with only one CAS RN. Only other Chemical names that have the exact set of CAS RN's are defined as synonyms. For example In these registries, calcium phosphate is identified with four different RNs, 7758-87-4, 10103-46-5, 12167-74-7, and 7758-23-8.
Most Materials are not a unique composition lending itself to a common database, like the Chemical Abstract Service Registry Numbers. Synonyms of Materials can come in many forms:
- National and international standard define abbreviations (ISO 1043-1 Plastics -- Symbols and abbreviated terms; ASTM D1600 ASTM Standard Terminology for Abbreviated Terms Relating to Plastics) Manufacturers have tradename products for these (FFKM -- ASTM, FFPM -- ISO, Chemraz -- Greene Tweede)
- For trademarks, if the product is identified as a common material name, we will identify it as a synonym.
For every Material name in a chemical resistance table in our database, we have found a reference that identifies the usage of the two terms defined as synonyms. For many chemical resistance tables there is a legend which indicates synonyms for the Material Name used in the table, which we use conservatively. When there is doubt, we do not assign synonyms.
Obviously Minor Differences
- When the name is an obvious arrangement of another name.
- PotassiumChloride is clearly Potassium Chloride
- Alcohol, ethyl is clearly the same as Ethyl Alcohol
- When there is a misspelling that is an obvious matching name that
unambiguously refers to a single chemical, such as
- Methyl ethyl keytone is obviously Methyl ethyl ketone
- Hydroflouric Acid is obviously Hydrofluoric Acid
- Misspellings: like "Ehtylene Propylene" or "Polysterene"
Names without Obvious Synonyms
For names that are not identified by our process below, we have eliminated those that that are ambiguous (example: ), names that are not identifiable chemicals, but appear to be (example: diethyltriamine - diethylenetriamine or diethylamine?), or not chemicals (example: methyl), and other entries that are not.
When a Source Document Combines Multiple Names
Infrequently, one of DCRG's reference documents will list more name in the header. As rare as this is, it requires consideration.
Headers listing multiple synonyms, such as Isobutylene-isoprene IIR, for which Isobutylene-isoprene and IIR (redundantly) refer to Butyl. Another example of the same situation would be Alcohol: Propyl (Propanol) which refers to Propanol twice.
Rarely an entry in a source table will list multiple items in the same row. Jet Fuel (JP3, 4, 5) and Stainless Steels-Type 304/307, are both assumed to mean each individual entity and not mixtures a mixture of them.
When there is doubt, we don't make assumptions.
CAUTION: All ratings, from DCRG or published tables, should be used ONLY as a guide. We assume no liability for the accuracy of any Rating, either in individual references we use or our average rating. As noted in out Caution on all DCRG tables:
All ratings should be used ONLY as a guide. as resistance is influenced by many variables, such as temperature, concentration, etc. We assume no liability for the accuracy of any Rating. The user should test any chemical and material under actual operating conditions to determine suitability.
Identifying synonyms allows DCRG to find more Ratings for your required Chemical/Material combination, without you needing to know there are synonyms for your substance of interest. This provides you with more Ratings and more confidence in the results you are seeking.
When there is doubt, we don't make assumptions.