diff --git a/src/systems/iec80000/include/mp_units/systems/iec80000/quantities.h b/src/systems/iec80000/include/mp_units/systems/iec80000/quantities.h
index 01c05cf3..ef0724ed 100644
--- a/src/systems/iec80000/include/mp_units/systems/iec80000/quantities.h
+++ b/src/systems/iec80000/include/mp_units/systems/iec80000/quantities.h
@@ -45,7 +45,7 @@ QUANTITY_SPEC(waiting_probability, dimensionless);
 QUANTITY_SPEC(call_intensity, 1 / isq::duration);
 inline constexpr auto calling_rate = call_intensity;
 QUANTITY_SPEC(completed_call_intensity, call_intensity);
-QUANTITY_SPEC(storage_capacity, dimensionless);
+QUANTITY_SPEC(storage_capacity, dimensionless, is_kind);
 inline constexpr auto storage_size = storage_capacity;
 QUANTITY_SPEC(equivalent_binary_storage_capacity, storage_capacity);
 QUANTITY_SPEC(transfer_rate, storage_capacity / isq::duration);
diff --git a/src/systems/iec80000/include/mp_units/systems/iec80000/units.h b/src/systems/iec80000/include/mp_units/systems/iec80000/units.h
index 8d63340d..3d05442d 100644
--- a/src/systems/iec80000/include/mp_units/systems/iec80000/units.h
+++ b/src/systems/iec80000/include/mp_units/systems/iec80000/units.h
@@ -30,7 +30,7 @@ namespace mp_units::iec80000 {
 
 // clang-format off
 inline constexpr struct erlang : named_unit<"E", kind_of<traffic_intensity>> {} erlang;
-inline constexpr struct bit : named_unit<"bit", one> {} bit;
+inline constexpr struct bit : named_unit<"bit", one, kind_of<storage_capacity>> {} bit;
 inline constexpr struct octet : named_unit<"o", mag<8> * bit> {} octet;
 inline constexpr struct byte : named_unit<"B", mag<8> * bit> {} byte;
 inline constexpr struct baud : named_unit<"Bd", 1 / si::second, kind_of<modulation_rate>> {} baud;
diff --git a/src/systems/isq/include/mp_units/systems/isq/space_and_time.h b/src/systems/isq/include/mp_units/systems/isq/space_and_time.h
index f71077ef..e3ef6769 100644
--- a/src/systems/isq/include/mp_units/systems/isq/space_and_time.h
+++ b/src/systems/isq/include/mp_units/systems/isq/space_and_time.h
@@ -45,11 +45,11 @@ QUANTITY_SPEC(radius_of_curvature, radius);
 QUANTITY_SPEC(curvature, 1 / radius_of_curvature);
 QUANTITY_SPEC(area, pow<2>(length));
 QUANTITY_SPEC(volume, pow<3>(length));
-QUANTITY_SPEC(angular_measure, arc_length / radius);
+QUANTITY_SPEC(angular_measure, dimensionless, arc_length / radius, is_kind);
 QUANTITY_SPEC(rotational_displacement, angular_measure, path_length / radius);
 inline constexpr auto angular_displacement = rotational_displacement;
 QUANTITY_SPEC(phase_angle, angular_measure);
-QUANTITY_SPEC(solid_angular_measure, area / pow<2>(radius));
+QUANTITY_SPEC(solid_angular_measure, dimensionless, area / pow<2>(radius), is_kind);
 inline constexpr auto duration = time;
 QUANTITY_SPEC(speed, length / time);                         // differs from ISO 80000
 QUANTITY_SPEC(velocity, speed, position_vector / duration);  // vector  // differs from ISO 80000