Air sampling & DAC screening help

This module provides air sampling calculation and documentation support for screening and training. It does not replace approved air sampling procedures, respiratory protection program requirements, DAC/ALI compliance assessment, effluent monitoring requirements, bioassay interpretation, or qualified health physicist review.

Open the workspace at /calculators/air-sampling. Hash fragments #sample-volume, #air-concentration, #dac-fraction, #dac-hours, #filter-count, and #grab-sample select each tool. Tabs use the shared workspace accessibility pattern (arrow keys, roving tabindex, aria-controls).

• Sample volume: average flow × time with L/min, mL/min, ft³/min, or m³/h flow units and minutes or hours. No temperature or pressure correction.
• Air concentration: collected activity divided by sample volume; outputs Bq/m³ and pCi/L. Optional notes capture detector path or filter recovery assumptions—they do not change the numeric result here.
• DAC fraction: concentration ÷ declared DAC (Bq/m³ or µCi/mL after internal conversion). User-supplied DAC requires a DAC source note for JSON / Markdown / copy export. The workspace shows DAC provenance: whether the DAC path is tabulated (Appendix B / licensee-table) vs user-supplied, the confidence tier (validated through placeholder), the effective source note (tabulated empty note is filled with a default traceability string for the shared physics layer), and an optional reference id. Placeholder or illustrative confidence triggers strong in-app warnings; it does not by itself block export when required notes are present.
• DAC-hours: screening DAC-hours reuse computeDacHours from internal dose after mapping concentration to Bq/m³. Optional respiratory protection factor (≥ 1) divides DAC-hours. Tabulated origin may leave the DAC note blank; the same default traceability string as DAC fraction is applied for the internal helper—document your table revision in records or in the optional note field.
• Filter count: gross − background to net cpm (or counts ÷ live time), then dpm and Bq with declared efficiency and a geometry/recovery factor. If the correction factor is not 1, a source note is required to export.
• Grab sample: short-duration field documentation; optional concentration from direct entry or activity ÷ volume. A non-empty source / procedure note is required for validity and export. For radionuclide, prefer From catalog (shared nuclide picker); Free text is only for designations that are not catalog rows and requires a separate nuclide source / procedure note before export when free-text text is entered. Reports include nuclideMode, nuclideId, and nuclideCatalogSymbol when the catalog resolves.

• User-supplied DAC: DAC source note required.
• Grab sample: procedure / source note required.
• Grab sample: free-text radionuclide with non-empty text → dedicated nuclide source / procedure note required (export gate).
• Filter count: source note required when correction factor ≠ 1.

Illustrative or placeholder DAC confidence produces strong warnings and elevates the report warning level for visibility; exports may still proceed when required documentation fields are satisfied. See /help/reports for general export validation.

• No respiratory protection program management.
• No certified internal dosimetry.
• No bioassay interpretation.
• No effluent compliance decision logic or plume modeling.
• No regulatory dose assignment or pass/fail against limits beyond user-entered DAC comparisons.

Reports may cite 10 CFR Part 20 Appendix B (ALI/DAC tables), NIST SI guidance, and an in-app screening note. The app does not ship operational DAC values as validated limits—users must cite current licensee or regulatory tables.