ShelterFactor knowledge base
Scientific Basis
ShelterFactor is intended to make the reasoning behind recommendations inspectable: assumptions, physical mechanisms, source hierarchy and limitations should be explicit.
Source hierarchy
Technical content preferentially uses primary and authoritative material. For Dutch emergency guidance this includes RIVM and Rijksoverheid; international radiological-protection and emergency-preparedness concepts are checked against IAEA safety standards and guidance.
What official guidance says
RIVM identifies sheltering, evacuation and iodine prophylaxis as examples of direct protective measures in a radiological emergency. It distinguishes direct exposure pathways such as inhalation and external irradiation from indirect pathways such as the food chain.
Rijksoverheid describes sheltering during a nuclear accident as going or remaining indoors and closing doors, windows and ventilation openings, while following official information. Iodine tablets are only to be taken when instructed by the authorities.
IAEA emergency-preparedness guidance treats sheltering as an urgent protective action. International guidance also recognises that sheltering can reduce both inhalation exposure and external exposure, while its effectiveness and appropriate duration depend on the emergency conditions.
From public guidance to engineering
Official public instructions are intentionally simple. ShelterFactor adds an engineering layer without presenting that layer as official policy. It asks what measurable performance a particular dwelling can provide and what upgrades change that performance.
Protection-factor framework
PFair is used conceptually for reduction of an airborne exposure pathway. PFฮณ represents reduction of external gamma exposure. Tautonomy represents the duration for which the protected environment can remain functional under stated assumptions.
The generic protection-factor form is PF = Doutside / Dinside. The numerator and denominator must refer to the same defined exposure quantity, time interval and scenario.
Engineering extensions are labelled as such
The ShelterFactor SF-0 to SF-5 maturity scale is an internal conceptual framework. It is not an ANVS, RIVM, IAEA or other regulatory classification. Likewise, extended autonomy targets are design choices unless an authoritative source explicitly states otherwise.
Primary references
- RIVM โ Gevolgen en maatregelen bij stralingsincidenten en kernongevallen
- Rijksoverheid โ Hoe kan ik mezelf beschermen bij een kernongeval?
- Rijksoverheid โ Jodiumtabletten bij een kernongeval
- IAEA โ Preparedness and Response for a Nuclear or Radiological Emergency
Limitations
Protection performance is scenario- and building-dependent. A numerical value without a defined source term, geometry, time basis and measurement or calculation method can be misleading. ShelterFactor is an independent technical platform and is not a regulator, government authority, emergency service or certification body.