2.4 Material Compliance: RoHS, REACH, & Conflict Minerals

Material compliance is not a "green initiative"; it is a binary gate for market entry. A single non-compliant capacitor (costing $0.01) containing > 1,000 ppm of Lead (Pb) can legally trigger a recall of millions of dollars of finished product in the EU or California. The objective is to architect a "Compliance Firewall" that prevents restricted substances from entering the manufacturing stream. Reliance solely on supplier certificates is insufficient; paper protects the supplier, not the product.

RoHS (Restriction of Hazardous Substances)

RoHS deals principally with heavy metals and flame retardants. For electronics manufacturing, the primary adversary is Lead (Pb).

Process Control Logic:

The risk of RoHS failure is highest at the Process Level, not just the Component Level. Mixing leaded and lead-free processes is the most common cause of non-compliance.

• IF the facility runs "Mixed Technology" (Leaded and Lead-Free):
  • THEN Rigid segregation is mandatory. Solder pots, rework irons, and tip cleaners must be color-coded and physically separated.
  • Control: Periodic XRF (X-Ray Fluorescence) screening of solder pots to verify Pb < 0.1%.
• IF a component claims an "Exemption" (e.g., 7c-I, Lead in Glass/Ceramic):
  • THEN Verify the expiration date of that exemption. Exemptions are not permanent rights.

Pro-Tip: "RoHS Compliant" does not always mean "Lead-Free." It means "Lead within legal limits or exempted." Always check the Datasheet for the specific termination finish (e.g., Matte Sn vs. SnPb).

REACH (SVHC List)

Unlike RoHS (which restricts 10 substances), REACH monitors hundreds of Substances of Very High Concern (SVHC). The list updates every six months.

The 0.1% Threshold Rule:

Compliance is defined by the weight of the SVHC relative to the weight of the "Article" (the simplest component part).

• IF an SVHC is present > 0.1% w/w (weight by weight):
  • THEN It is not necessarily banned, but it MUST be declared in the SCIP Database (Substances of Concern In products).
  • Action: Screen Bill of Materials (BOM) against the current Candidate List (updated June/Dec).

Conflict Minerals (3TG)

This is an ethical supply chain mandate (Dodd-Frank Act / EU Regulations). It targets four minerals sourced from high-risk zones: Tin, Tantalum, Tungsten, Gold (3TG).

The Verification Tool: CMRT

The Conflict Minerals Reporting Template (CMRT) is the industry standard for tracking the chain of custody.

• IF a supplier cannot provide a valid CMRT:
  • THEN The supply chain is opaque. Flag as High Risk.
• IF the smelter list includes known conflict sources:
  • THEN Alternative sourcing is required immediately.

The Quality Gate: Inspection Strategy

100% chemical analysis is inefficient. Use a risk-based sampling plan at Incoming Quality Control (IQC).

Decision Logic for Incoming Inspection:

1. Distributor Source (Tier 1):
   • Action: Verify CoC (Certificate of Compliance) matches the Part Number.
   • Risk: Low.
2. Broker / Independent Distributor (High Risk):
   • Action: MANDATORY XRF Screening.
   • Logic: Brokers often mix date codes or re-reel old inventory (pre-RoHS).
   • Threshold: If Pb detected > 700 ppm (warning) / > 1000 ppm (fail).
3. Plastic/Enclosure Parts:
   • Action: Verify Phthalates (DEHP, BBP, DBP, DIBP).
   • Logic: These are common softeners in wire insulation and housings, heavily restricted under RoHS 3.

Final Checklist

Regulation	Target Substance	Critical Threshold	Control Action
RoHS 3	Lead (Pb)	< 1,000 ppm (0.1%)	XRF Screen High-Risk Parts
RoHS 3	Cadmium (Cd)	< 100 ppm (0.01%)	Check contacts/platings
REACH	SVHC List	< 0.1% w/w	Check BOM vs. Candidate List
Conflict Min.	3TG (Tin/Gold/etc.)	Smelter Verification	Request CMRT from Supplier
Process	Solder Pot Contamination	Pb < 0.1%	Lab Analysis (Quarterly)
Documentation	CoC / Declaration	Must cite Standard	Match Rev to Purchase Order