Contamination & Internal wipe_test_calc
Removable Surface Contamination (Wipe / Smear)
Standardizes contamination surveys per 10 CFR 20 and DOT 49 CFR 173, converting laboratory smear counts into dpm/100 cm² and Bq/cm² to verify regulatory release limits.
C_dpm = (R_gross − R_bkg) / [ε_det × E_wipe × (A_wipe / 100)]
RADCALC HEALTH PHYSICS & NUCLEAR ENGINEERING WORKSHEET
Removable Surface Contamination (Wipe / Smear) (Wipe Test)
Domain: Contamination, Air Sampling & Internal Dosimetry · Tool ID:
wipe_test_calc · Engine: 100% Local Browser WASM C_dpm = (R_gross − R_bkg) / [ε_det × E_wipe × (A_wipe / 100)]
Operational Notes:
Guided Stepper Workflow All Input Parameters & Solver
1
What do you want to calculate?
Select your target output variable. The stepper will guide you through only the required inputs.
2
Start from a Field Scenario Preset (Optional)
Pre-fill realistic health physics values, then refine individual parameters or jump straight to the result.
All Parameters Entered
Review Inputs & Calculated Result
Solved Output Live WASM Readout
-- --
Entered Input Parameters (Tap any row to edit)
Calculated Result & Visual Analysis
Nominal Solved Value Updated automatically
--
--
Enter parameters on the left to calculate.
CLIENT-SIDE 3D SIMULATION Removable Surface Contamination (Wipe / Smear) 3D Transport Field
Interactive 3D Geometry & Particle Transport
WebGPU / WebGL2 Ready
3D Hardware Acceleration & Browser Compatibility Status Inspect Requirements ↓
Checking Browser 3D Capabilities… Probing WebGPU adapter, WebGL 2.0, and WebGL 1.0 contexts locally.
Geometry & Field Diagram
Interactive Model
Sensitivity Curve
Normalized Base-Unit & WebMCP Tool Payload wipe_test_calc
1. Input & Solved Parameter Ledger
| Role | Symbol | Parameter Name | Entered / Display Value | Normalized Base Unit | Definition |
|---|
2. MARSSIM & NRC Reg Guide 1.86 Smear Log
Governing Equation & Parameters
Removable Activity (dpm/100 cm²) = Net CPM / (Detector Efficiency × Wipe Pick-up Efficiency × Area/100)
| Symbol | Parameter | Default Unit | Definition |
|---|---|---|---|
| R_g | Gross Smear Count Rate | cpm | Observed count rate on the smear sample in counts per minute. |
| R_b | Background Count Rate | cpm | Instrument background count rate in counts per minute. |
| R_net | Net Sample Count Rate | cpm | Net smear count rate (gross cpm − background cpm). |
| ε_det | Counter 2π/4π Efficiency | fraction | Detector counting efficiency for the radionuclide emissions (0.05 to 0.6). |
| E_wipe | Wipe Collection Efficiency | fraction | Fractional smear collection pickup factor (standard regulatory default 0.10). |
| A_wipe | Surveyed Surface Area | cm2 | Total surface area wiped in square centimeters (standard 100 cm²). |
| C_dpm | Removable Contamination | dpm/100cm2 | Removable activity density in disintegrations per minute per 100 cm². |
| C_Bq | Surface Activity Density | Bq/cm2 | Removable surface contamination density in Becquerels per cm². |
Health Physics Notes & Related Calculators
Operational Guidance & Physics Assumptions
- Standard health physics protocol assumes a default 10% (0.10) wipe pickup efficiency per 10 CFR 20.1501 and ISO 7503.
- Regulatory unrestricted action levels: 2200 dpm/100 cm² (0.37 Bq/cm²) for beta/gamma/low-toxicity alpha; 220 dpm/100 cm² (0.037 Bq/cm²) for high-toxicity transuranic alphas (Pu-239, Am-241).
- Standard surface smear area is 100 cm² (a nominal 10 cm × 10 cm square or 4-inch S-stroke).
More in Contamination, Air Sampling & Internal Dosimetry (3)
Explore All Other Radiation Domains (24 Calculators) Expand ↓
-- --