Positive Pressure Laboratory
Clean-space infrastructure for low-level environmental measurements, method development, and high-resolution mass spectrometry.
Building verified capability in stages.
The PPL is home to a Thermo Scientific Element XR high-resolution inductively coupled plasma mass spectrometer acquired through NSF Major Research Instrumentation award 2511702. The system will expand UAF capacity for precise elemental concentration and isotope-ratio measurements at low concentrations.
Draft 0.3 · August 19, 2026
Planned analytical offerings
The PPL intends to develop four named, matrix-specific methods rather than advertise a universal trace-elements analysis. The draft menu below identifies the samples, focused analyte suites, preparation routes, and analytical depth the facility is being built to support.
Analytical depth
Four tiers of work
The method code defines the matrix and analytes. The tier defines the preparation, quality control, review, and reporting supplied for a project. Available tiers will be published separately for each verified method.
Tier 1
Screening survey
Purpose: exploratory elemental surveys, sample triage, and method scouting.
Typical input: approved, instrument-ready dilute-acid solutions or digests.
Planned output: concentration estimates, detected/not-detected flags, and an abbreviated batch-control summary. Screening results would not carry the full claims of a verified quantitative method.
Tier 2
Standard quantitative
Purpose: routine research samples that fit a verified matrix-specific method and reporting range.
Planned controls: multi-point calibration, second-source verification, method blank, appropriate reference material or matrix spike, duplicate, continuing calibration checks, and documented acceptance rules.
Planned output: reviewed concentrations, units, qualifiers, method reference, and batch quality-control summary.
Tier 3
Enhanced quantitative
Purpose: demanding matrices, lower target concentrations, or projects requiring stronger project-specific evidence.
Possible additions: matrix separation or preconcentration, replicate preparation, additional reference materials and spikes, isotope or resolution confirmation, narrower contamination controls, and a project-defined uncertainty assessment.
Access: scoped with facility staff before sample collection.
Tier R
Collaborative research
Purpose: unsupported matrices or analytes, new preparation chemistry, isotope-ratio work, speciation, coupled techniques, and other method development.
Structure: a jointly planned research activity with explicit development time, controls, decision points, data interpretation, and funding. A successful project may later become a standard offering.
Initial portfolio
Four methods being developed
| Code and status | Offering | Focused development panel | Candidate matrices and preparation | Likely tiers |
|---|---|---|---|---|
| TAG-TE01 Proposed · Priority 1 | Trace elements in waters and dilute extracts | Focused subset of the EPA 200.8 analyte suite; mercury is excluded from the initial XR panel | Freshwater, river water, snow or ice melt, permafrost leachates, and dilute acid extracts that meet verified turbidity, salinity, and dissolved-solids limits; filtered or total-recoverable claims will be method-specific | 1, 2, 3 |
| TAG-TE3A Proposed · Priority 2 | Acid-extractable elements in sediments, soils, and particles | Focused subset of EPA 6020B demonstrated analytes; major matrix elements and mercury are excluded from the initial panel | Marine or freshwater sediment, suspended particles, soils, and permafrost solids; microwave-assisted nitric acid or nitric/hydrochloric-acid extraction informed by EPA 3051A | 2, 3 |
| TAG-RE01 Proposed · Priority 3 | Rare earth elements plus yttrium | Y and the lanthanide series, with Th and U evaluated as optional additions | Acid extracts and compatible sediment, soil, permafrost, or particle digests; aqueous matrices only after matrix-specific verification | 2, 3, R |
| TAG-SP01 Proposed · Priority 4 | Phosphorus and sulfur | P and S | Selected biological, sediment, soil, permafrost, or particle digests and low-matrix aqueous samples; not a replacement for routine dissolved nutrient analysis | 2, 3, R |
Panels are development targets. Final reportable elements, isotopes, resolution, preparation, working range, detection capability, sample volume, preservation, and exclusions will be method-specific. The detailed Element XR page records the current candidate analytes without crowding this overview.
What changes as methods mature
The stable parts
Method codes identify a scientific claim and matrix family. They allow proposals, documentation, data systems, and future publications to refer to the same offering even as its version advances.
Every released method will state exactly which preparation, analytes, matrices, and tiers it supports.
The versioned parts
Panels, reporting ranges, detection capability, sample requirements, batch size, price, turnaround, quality-control limits, and availability can change as evidence and capacity improve. Material changes will receive a new method version and date.
Projects outside a released scope remain Tier R rather than being forced into an unsuitable routine method.
Outside the initial routine menu
Biological-tissue panels, total silicate digestion, dissolved trace metals in seawater or saline brines, total mercury, seawater rare earth elements, isotope ratios, chromatography and speciation, laser ablation, and other coupled applications are not part of the four-method initial portfolio. They may be considered as Tier R collaborations when the necessary preparation, standards, interfaces, expertise, and project support are available.
Planning a future project
Discuss projects with the team before writing a proposal, collecting samples, or promising analyses. Early conversations should cover the scientific question, requested method and tier, target analytes, expected concentrations, matrix, salinity or dissolved solids, available sample volume, preparation and preservation, contamination control, reference materials, number of samples and controls, data requirements, schedule, and funding.