Testing by Vanguard Laboratory · Olympia, Washington360-967-7010

General chemistry

SM 3500-Fe B: Ferrous iron

Scope SM 3500-Fe B for ferrous iron. Define sample matrix, preparation, reporting limits and project requirements.

Ferrous iron measurement context

Standard Methods 3500-Fe B, phenanthroline: ferrous iron forms an orange-red complex with 1,10-phenanthroline that is measured by spectrophotometry. The reducing step used for total iron is left out, so only the ferrous form is counted. Ferrous iron oxidizes in air, so contact us before sampling. Reported as mg/L iron.

Define where the property is measured

Specify field or laboratory measurement, units and the sample state needed for the project. A delivered sample may not preserve the source-time condition for a changing property.

Include the complete project requirement

Provide the matrix, target analytes, required method, fraction, units and reporting limits. Include the permit or monitoring instructions where results will support a regulatory submission. Naming this method does not establish blanket compliance eligibility.

Resolve collection before sampling

Use the bottle, preservation and delivery instructions assigned to the agreed scope. Identify each location and collection time, and document any deviation. The final analytical plan must fit the submitted material and its intended use.

Related testing & guidance

Technical & service references

Vanguard service details

Source review: November 8, 2026. The agreed method and project scope govern the testing.

Start with a defined scope

Build a project scope

Tell us the sample, the question and the decision your results need to support.

Build a testing request