# Source–Transport–Receptor Chain
**Entity class:** Hazard-modeling sequence
## Definition
The **source–transport–receptor chain** separates the origin of a hazard, its propagation through an environment, the resulting field, the exposed receptor, dose or contact, biological or system response, and operational consequence.
This separation prevents a field model from being mistaken for a completed individual-effects model.
## Relationships
- **source and propagation:** [[wiki/Neutron Transport Equation|Neutron Transport Equation]] and [[wiki/Radiation Transport Field|Radiation Transport Field]].
- **endpoint:** [[wiki/Receptor Layer|Receptor Layer]], [[wiki/Absorbed Dose|Absorbed Dose]], and [[wiki/Exposure Pathway|Exposure Pathway]].
- **scale transition:** [[wiki/Theater-to-Person Predictive Scale|Theater-to-Person Predictive Scale]].
## Sources / Provenance
- [Oden Institute — DTRA radiation-effects project, December 5, 2017](https://oden.utexas.edu/news-and-events/news/minimizing-uncertainty-in-uncertain-world-of-defense-energy/)