Only substances that remain in the product should be declared in the material declaration file. Manufacturing chemicals that react, form other chemicals or otherwise do not remain in the product should not be reported. However, in some cases, a chemical reaction may not be complete and some unreacted quantity of an intermediate chemical may remain in the finished product. These chemicals may be reported; in fact, if the intermediate chemical is listed in the IEC 62474 declarable substances list and a quantity above the reporting threshold could reamin in the final product, then it has to be reported m– otherwise the material declaration will not conform with the IEC 62474 requirements.

A common example is the resin and a hardener used to form epoxy. The final epoxy substance must be declared if it is a declarable substance or as a voluntary declaration if it isn’t. The individual resin and hardener chemicals would not be declared unless a residual amount of the chemical remains in the product and then only the residual amount would be declared.

A user may only state that they are in conformance with IEC 62474 if they have included all reportable substances and substance groups that are present in the product above the reporting threshold.

Substances with a CAS-number that contain other substances sometimes cause confusion in a material declaration. The CAS-number system does not exclude the possibility that a substance with a CAS-number consists of a number of other substances with CAS-numbers. Examples are:

• Steel with CAS number 12597-69-2
• Brass with CAS number 12597-71-6

Each of these substances have a variable composition and may or may not include a reportable substance such as Lead (Pb). Declaring only “Steel” does not give information if lead is a constituent of the alloy or not. If a mixture (whether a solid (e.g. metal alloy), liquid, or gas) contains a declarable substance or declarable substance group, then this declarable substance or declarable substance must always be explicitly reported if present above the reporting threshold and if the reportable application is met.

Another issue that sometime arises in material declarations is when a supplier lists the elements that make up a compound rather than reporting the chemical compound itself. Many declarable substances are compounds which must be reported as listed in the IEC 62474 list of declarable substances. IEC 62474 does not allow the material declaration to report the separate elements that make up the compound. For example Disodium tetraborate, decahydrate (Borax) (CAS-number 1303-96-4 ) consists of Sodium, Boron and Oxygen, with CAS-numbers 7440-23-5, 7440-42-8.and 7782-44-7. Using these elemental CAS-numbers in the declaration will hide the existence of the declarable substance and violates the reporting requirement of IEC 62474.

Mass information needs to be provided for each of elements in a material declaration that correponds to a physical object or chemical (ie. product, product part, material, substance group, and substance in the figure below). The product element sits at the top of the declaration hierarchy therefore it must always include the mass (a mass percent would be meaningless). For the other elements, the responder who is creating a material declaration generally may provide either the mass or the mass percent.

Conceptual Material Declaration with Optional Declaration of Product Parts and Materials

Mass percent is calculated relative to the element above it in the material declaration. For example, the mass percent of material X is calculated relative to the mass of Product part 1 and the mass percent of Product part 1 is calculated relative to the mass of Product. An exception to the above rule is that the mass percent of substances and substance groups are both calculated relative to the material (or product part / product if material is not declared). A substance mass percent is never calculated relative to the mass of a substance group. This is because substance groups are often unusual grouping of substances and the mass may represent only a part of the substance molecules. For example, Lead/Lead Compounds only considers the Lead atoms and not the entire mass of lead compounds.

If the reporting threshold of a substance or substance group is based on the material (e.g. the RoHS substance thresholds), then the the MatMassPercent element must be used to capture the mass information.

This guidance document recommends that material declarations include any regulatory exemptions that are applicable to the use of declarable substances and declarable substance groups. Once declared, the standard requires that information about exemptions, must be carried through the supply chain (subclause 4.3.4(f)). Users should check the reportable application to assess whether an exemption is applicable or not to a given application

The IEC 62474 standard is very flexible in allowing users to specify exemptions from one or a multiple of exemption lists. For example, a material declaration may specify both an EU RoHS exemption and simultaneously an EU ELV exemption for a given use of lead. Exemptions may be specified for a substance, a substance group or at the level of the entire product. In most cases, exemptions will be associated with the substance or substance group. The IEC 62474 XML schema does not currently allow exemptions to be associated with product parts or materials.

Users should use exemptions from a recognized and maintained list that is readily available and commonly accepted throughout the electrotechnical industry and supply chain. This is necessary to allow computer processing of the exemptions in the material declaration XML file. Examples of such maintained lists include the IPC 1752 standard and the JAMP material declaration system. Examples of declaring such exemptions are provided in Clause 4 of this guidance document. Within the material declaration file, each Exemptions entry has data fields for “UniqueID” (provides information about the exemption list used) and “Exemption” which identifies the specific exemption that is applicable. The UniqueID field will include the authority — use the exact text string provided by the authority (e.g. IPC) — and the specific exemption list that is used (e.g. see IEC 62474 exemption lists published on the IEC 62474 database). The “Exemption” field will include the identity of the exemption (e.g. ee IEC 62474 exemption lists published on the IEC 62474 databaseand the text based description of the exemption. All of these fields should be copied verbatim from the maintained exemption list that is used. Detailed XML examples of exemptions are provided in clause 4

The IEC 62474 Declarable Substance List (DSL) is a list of regulated substances and substance groups (e.g. lead and lead compounds) that a manufacturer should declare to downstream manufacturers if present in the product. Each substance or substance group entry in the list is accompanied with a reportable application and a reporting threshold level. The supplier that is creating the material declaration will use this information to determine if the substance must be declared.

The DSL may be accessed from the IEC 62474 database via the menu bar on the left side of the introduction webpage – click on “Declarable substance groups and declarable substances” and then select the substance from the drop down list. For example, selecting “Lead/Lead Compounds” presents five entries with different reportable application / reporting threshold combinations – the first entry corresponds to the RoHS restriction. Clicking on the “Details” button reveals information about reference substances; typical EEE applications, regulations, and other information.

There is also an option on the website to export the entire DSL.

For most of the declarable substance and declarable substance group entries in the IEC 62474 database, the reporting threshold is based on the mass percent of the product. This is represented by a reporting threshold that is listed as “0.1 mass%”. The reference to the mass of the product that is declared is implied in this threshold. However, there are other many declarable substances and declarable substance groups that have a reporting threshold that has a different calculation basis. The EU RoHS declarable substance groups are examples that use the mass of the homogeneous material as the basis for calculation.

The IEC 62474 developer’s table includes a column (Obligation column) that indicates whether a specific data field (element or attribute) is mandatory or optional. Some data fields are listed as conditional. These fields are mandatory under certain material declaration conditions and optional under other conditions.

For example, Mass, MassPercent, and MatMassPercent are all listed as conditional. At least one of these data fields must be provided in a valid material declaration. The obligation column for Mass and MassPercent states: “Conditional (Either Mass or MassPercent is mandatory unless otherwise specified in IEC 62474 database)”. Basically, the data field is mandatory unless the information has been provided in one of the other mass related data fields. For most substance declarations, the supplier that is filling out the material declaration can decide whether they would like to provide the mass of the substance or the mass percent (weight/weight) of the substance.

The obligation description indicates that information provided in the IEC 62474 database may specify exactly which of these data fields needs to be provided. The most common situation for this is the EU RoHS substance groups which must be reported as a mass percent of the homogeneous material. In this case, the MatMassPercent element must be used to capture the mass information.

For substances that may be reported as a mass or mass percent, the standard technically allows the supplier to provide both data fields, but this is generally not recommended.  Experience with material declarations has shown that it’s easy to introduce errors (including rounding errors) when providing both numbers. This leaves the recipient of the material declaration uncertain as to which data field is actually correct.

June 30, 2014 update:  To prevent inconsistency between mass and mass percent information, the interpretation of allowing both mass and mass percent to be declared is being changed for the upcoming X5.00 version of the schema/developer’s table. The update will allow only mass or mass percent to be provided. X5.00 is forecast to be published in the fall of 2014 — an additional blog post will be provided when the new data exchange format is published on the IEC 62474 database.