ECRR – The 2026 Radiation Risk Model (includes Depleted Uranium)

ECRR 2026 Risk Simulator – v5

Corrected unit scaling · 1 Mü = 1 Sv (confirmed by C. Busby, Aug 2026) · GeneForge AI Labs

Unit correction applied (Aug 2026):
Chris Busby confirmed: 1 Mü (Müller) = 1 Sv, not 1 mSv.
Therefore the conversion Genetic Dose (Mü) → ERR now uses the factor corresponding to Sv-scale coefficients from Table 2.1
(previously the simulator incorrectly treated 1 Mü ≈ 1 mSv, understating risk by a factor of 1 000).

Parameters

Dose (mSv)

Exposure scenario External gamma/X (biphasic Table 2.1) Internal – mixed fission products (Table 2.2) Internal – Uranium / DU particles Generic alpha (weighting 200)

Population size

Specific Radionuclide – Table B3 (already includes WJ × WK)

Radionuclide H-3 (Tritium) C-14 Sr-90 Cs-137 I-131 Pu-239 * U-238 * Am-241 * Ra-226 *

Pathway Inhale Ingest Particle Inhale <10 µm Particle Ingest >10 µm

Activity (Bq)

Population

* Alpha emitters – coefficients already include the ECRR alpha weighting of 200.
Conversion: Genetic Dose (Mü) is treated as Sv (1 Mü = 1 Sv). ERR ≈ Genetic Dose × 12 (derived from Table 2.1 low-dose coefficient 0.12 per 10 mSv = 12 per Sv).

Depleted Uranium Scenario

Mass of DU (tonnes)

Aerosolised fraction (% that becomes respirable <10 µm)

Exposed population

Specific activity of U-238 / DU ≈ 12.4 MBq/kg = 1.24 × 10¹⁰ Bq per tonne.
Coefficient used: Particle Inhale <10 µm = 0.435 Mü/Bq (Table B3).
1 Mü = 1 Sv (Busby confirmation, Aug 2026).

Critical assumptions: This calculation only estimates the Genetic Dose that would result if the chosen fraction of the DU mass is fully converted into respirable particles and then fully available for inhalation by the exposed population. Real atmospheric dispersion, dilution, particle settling and actual intake fractions are not modelled. The result is therefore an upper-bound / order-of-magnitude illustration, not a realistic environmental dose reconstruction.

Illustrative Worked Examples (corrected scaling)

Example 1 – 1 Bq Pu-239 particle inhale
Coefficient: 0.075 Mü/Bq → Genetic Dose = 0.075 Mü = 0.075 Sv
ERR ≈ 0.075 × 12 = 0.90 → 90% Excess Relative Risk

Example 2 – 1 tonne DU, 5% aerosolised
Activity ≈ 1.24e10 Bq × 0.05 = 6.2e8 Bq
Genetic Dose = 6.2e8 × 0.435 ≈ 2.70e8 Mü = 2.70e8 Sv
This order of magnitude illustrates why the draft describes certain uranium particle exposures as “effectively infinite”.

Note on previous (incorrect) scaling
The earlier version treated 1 Mü ≈ 1 mSv and used ×0.012. That understated all Genetic-Dose-based risks by a factor of 1 000. The present version follows Busby’s explicit statement that 1 Mü = 1 Sv.

Key clarifications (updated Aug 2026)

1 Mü (Müller)	1 Sv (confirmed by C. Busby, August 2026)
Conversion Mü → ERR	Apply external coefficients of Table 2.1 treating Mü numerically as Sv Low-dose region: 0.12 per 10 mSv → 12 per Sv
Table B3 includes WJ × WK?	Yes (page 218)
Alpha weighting	200 (already included in * coefficients)
Uranium particles	Draft describes hazard as extremely high / “effectively infinite” in some contexts
Table 2.2 (mixed fission)	Pragmatic coefficient ERR 5.2 per 10 mSv remains preferred for real-world mixtures (independent of Mü path)

Important: Educational implementation of the ECRR 2026 draft.
Unit scaling corrected after direct confirmation from Chris Busby that 1 Mü = 1 Sv (not 1 mSv).
The DU module remains highly sensitive to the aerosolisation and intake assumptions and must not be interpreted as a realistic environmental impact assessment.

Source: ECRR – The 2026 Radiation Risk Model (Draft for Comment). Table 2.1, Table 2.2, Table B3.
Unit clarification: C. Busby, private communication, August 2026.
Tool developed by GeneForge AI Labs · Independent research · v5 (corrected)