Chapter 5: Chemical Analysis ICP / ICP-MS

Water Quality — WIA-ENV-017

EPA Method 200.7 trace elements by ICP-AES (1µg/L typical detection), EPA Method 200.8 trace elements by ICP-MS (0.1 µg/L typical), QC per ICV/CCV/MS/MSD/method blank per 40 CFR 136.

This chapter elaborates on the Chemical Analysis ICP / ICP-MS portion of Water Quality (WIA-ENV-017). The water quality canonical envelope shape, API surface, and protocol exchanges are designed to interoperate across implementations published under the WIA Standards family. Each Phase file in `spec/` documents one architectural layer (envelopes, REST surface, federation, ecosystem) and the present chapter focuses on the chemical analysis icp / icp-ms subset of that layering.

Implementations of chemical analysis icp / icp-ms need to reconcile the per-standard expectations of WHO Guidelines for Drinking-water Quality 4th Edition + 1st Addendum 2017, US EPA National Primary Drinking Water Regulations 40 CFR 141, ISO 5667 series (Water sampling), ISO 7027 (Turbidity), EPA Method 200.7 / 200.8 (ICP / ICP-MS). The Phase 1 envelope class for Water Quality carries the per-host identifier and per-tenant identifier so that audit records can be reconstructed across hosts that federate through the Phase 3 protocol layer.

Operators stepping into chemical analysis icp / icp-ms typically follow this trajectory: stand up the reference simulator at `simulator/index.html`, walk the canonical envelope per the CLI helper at `cli/water-quality.sh envelope`, then exercise the Phase 2 endpoints with curl/Postman against a host running the reference container at `wia/water-quality-host:1.0.0`. Once those steps complete, integrators wire the real backend one endpoint at a time per the Phase 1 §A.* envelope catalogue and the Phase 2 §B.* endpoint catalogue.

A common operational concern in the chemical analysis icp / icp-ms space is observability. Every Phase 1 envelope SHOULD emit a structured log line at the host's audit transport with: timestamp per RFC 3339, host identifier, tenant identifier, envelope class, envelope identifier, operation outcome, and a W3C Trace Context `traceparent` propagated end-to-end. Phase 2 surfaces this trace identifier as the `X-WIA-Trace-Id` response header. Phase 3 protocol exchanges propagate the trace identifier inside the exchange envelope so that a federation crossing remains correlatable end-to-end.

The chemical analysis icp / icp-ms portion of the standard composes with: WIA-OMNI-API for credential storage, WIA-AIR-SHIELD for runtime trust list, WIA-INTENT for workload intent declaration, and WIA Secure Enclave for sealed-data envelopes where personal data is processed. The composition lets one host running multiple WIA family standards reuse one identity, one signing-key chain, and one audit transport rather than maintaining N parallel per-standard implementations.

Normative references touched in this chapter

Implementation worksheet

  1. Read the corresponding Phase file in spec/ (Phase 1 for envelopes, Phase 2 for API, Phase 3 for protocol, Phase 4 for ecosystem).
  2. Walk the CLI helper: ./cli/water-quality.sh envelope emits a sample Phase 1 envelope.
  3. Exercise the simulator at simulator/index.html.
  4. Cross-reference the standards listed above to align with the operator's per-jurisdiction obligations.
  5. Wire the conformance suite at https://github.com/WIA-Official/wia-water-quality-conformance.

Cross-standard composition recap

This chapter, like every other Phase 1-4 chapter in the Water Quality eBook, composes with the wider WIA Standards family. Implementations that adopt the canonical envelope reuse the cross-standard audit transport (W3C Trace Context plus OpenTelemetry semantic conventions), the cross-standard identity (WIA-OMNI-API), and the cross-standard runtime trust list (WIA-AIR-SHIELD) without per-standard re-implementation. The federation handshake described in Phase 3 §3 follows the same challenge-response pattern as the rest of the WIA Standards family so that one operator can federate across multiple standards using one signing-key chain and one audit transport.