Adding strahlenschutzverordnung waste limits

openmc/deplete/chain.py

@@ -1237,6 +1237,54 @@ def reduce(self, initial_isotopes, level=None):
 
         return new_chain
 
+    def get_decay_daughters(self, nuclide, max_half_life=None):
+        """Return all nuclides reachable via decay from a given nuclide.
+
+        Unlike :meth:`reduce`, this follows only decay paths (not
+        reactions such as neutron capture) and returns a set of nuclide
+        names rather than a new :class:`Chain`.
+
+        Parameters
+        ----------
+        nuclide : str
+            Name of the parent nuclide.
+        max_half_life : float, optional
+            Maximum daughter half-life in seconds. Stops descending a
+            branch when a daughter's half-life exceeds this value. If
+            None, all radioactive daughters are returned regardless of
+            half-life.
+
+        Returns
+        -------
+        set of str
+            Names of all decay daughters reachable from the parent.
+
+        """
+        daughters = set()
+        stack = [nuclide]
+        visited = set()
+        while stack:
+            name = stack.pop()
+            if name in visited:
+                continue
+            visited.add(name)
+            if name not in self.nuclide_dict:
+                continue
+            for mode in self[name].decay_modes:
+                target = mode.target
+                if target is None or target in visited:
+                    continue
+                if target not in self.nuclide_dict:
+                    continue
+                target_nuc = self[target]
+                if target_nuc.half_life is None or target_nuc.half_life <= 0:
+                    continue
+                if max_half_life is not None and target_nuc.half_life >= max_half_life:
+                    continue
+                daughters.add(target)
+                stack.append(target)
+        return daughters
+
     def _follow(self, isotopes, level):
         """Return all isotopes present up to depth level"""
         found = isotopes.copy()

openmc/material.py

@@ -1597,6 +1597,7 @@ def waste_disposal_rating(
         limits: str | dict[str, float] = 'Fetter',
         metal: bool = False,
         by_nuclide: bool = False,
+        chain=None,
     ) -> float | dict[str, float]:
         """Return the waste disposal rating for the material.
 
@@ -1630,6 +1631,37 @@ def waste_disposal_rating(
               short-lived radionuclides
             - 'NRC_short_C': Uses the 10 CFR 61.55 class C limits for
               short-lived radionuclides
+            The following options use clearance values from the German
+            Strahlenschutzverordnung (StrlSchV) 2018, Anlage 4, Tabelle 1.
+            These limits are in [Bq/g] and the material activity will be
+            compared using the same units.
+
+            - 'StrlSchV_unrestricted': Unrestricted clearance of solid and
+              liquid substances (column 3)
+            - 'StrlSchV_metal_recycling': Metal scrap recycling (column 14)
+            - 'StrlSchV_landfill_100': Landfill disposal for facilities
+              receiving ≤100 Mg/a (column 8)
+            - 'StrlSchV_landfill_1000': Landfill disposal for facilities
+              receiving ≤1000 Mg/a (column 10)
+            - 'StrlSchV_incineration_100': Incineration for facilities
+              receiving ≤100 Mg/a (column 9)
+            - 'StrlSchV_incineration_1000': Incineration for facilities
+              receiving ≤1000 Mg/a (column 11)
+            - 'StrlSchV_soil': Soil surface clearance (column 7)
+            - 'StrlSchV_rubble': Building rubble clearance for >1000 Mg/a
+              (column 6)
+
+            .. note::
+                Some nuclides in Anlage 4 are listed with a '+' suffix,
+                indicating that their clearance value includes daughter
+                nuclides in secular equilibrium. When a depletion chain is
+                provided via the ``chain`` parameter, daughters in secular
+                equilibrium are automatically excluded from the
+                sum-of-fractions to avoid double-counting. Without a
+                chain, all nuclides with clearance entries are counted
+                individually, which may overestimate the rating for some
+                decay chains.
+
         metal : bool, optional
             Whether or not the material is in metal form (only applicable for
             NRC based limits)
@@ -1639,6 +1671,11 @@ def waste_disposal_rating(
             nuclide names and the values are the waste disposal ratings for each
             nuclide. If False, a single float value is returned that represents
             the overall waste disposal rating for the material.
+        chain : openmc.deplete.Chain, optional
+            Depletion chain used to identify daughter nuclides in secular
+            equilibrium for StrlSchV limits. When provided, daughters
+            covered by a parent's '+' clearance value are excluded from
+            the sum-of-fractions to avoid double-counting.
 
         Returns
         -------
@@ -1651,7 +1688,7 @@ def waste_disposal_rating(
         Material.waste_classification()
 
         """
-        return waste._waste_disposal_rating(self, limits, metal, by_nuclide)
+        return waste._waste_disposal_rating(self, limits, metal, by_nuclide, chain)
 
     def clone(self, memo: dict | None = None) -> Material:
         """Create a copy of this material with a new unique ID.