diff --git a/src/systems/isq/include/mp-units/systems/isq/atomic_and_nuclear_physics.h b/src/systems/isq/include/mp-units/systems/isq/atomic_and_nuclear_physics.h
index 5753c325..7493e0f3 100644
--- a/src/systems/isq/include/mp-units/systems/isq/atomic_and_nuclear_physics.h
+++ b/src/systems/isq/include/mp-units/systems/isq/atomic_and_nuclear_physics.h
@@ -24,11 +24,15 @@
 
 #include <mp-units/quantity_spec.h>
 #include <mp-units/systems/isq/base_quantities.h>
+#include <mp-units/systems/isq/mechanics.h>
 #include <mp-units/systems/isq/space_and_time.h>
 
 namespace mp_units::isq {
 
 // TODO Add all the remaining ISQ definitions
 QUANTITY_SPEC(activity, 1 / duration);
+QUANTITY_SPEC(absorbed_dose, energy / mass);
+QUANTITY_SPEC(ionizing_radiation_quality_factor, dimensionless);
+QUANTITY_SPEC(dose_equivalent, absorbed_dose* ionizing_radiation_quality_factor);
 
 }  // namespace mp_units::isq
diff --git a/src/systems/si/include/mp-units/systems/si/units.h b/src/systems/si/include/mp-units/systems/si/units.h
index 7299e89a..b127018f 100644
--- a/src/systems/si/include/mp-units/systems/si/units.h
+++ b/src/systems/si/include/mp-units/systems/si/units.h
@@ -73,8 +73,8 @@ inline constexpr struct degree_Celsius : named_unit<basic_symbol_text{"°C", "`C
 inline constexpr struct lumen : named_unit<"lm", candela * steradian> {} lumen;
 inline constexpr struct lux : named_unit<"lx", lumen / square(metre)> {} lux;
 inline constexpr struct becquerel : named_unit<"Bq", 1 / second, kind_of<isq::activity>> {} becquerel;
-inline constexpr struct gray : named_unit<"Gy", joule / kilogram> {} gray;
-inline constexpr struct sievert : named_unit<"Sv", joule / kilogram> {} sievert;
+inline constexpr struct gray : named_unit<"Gy", joule / kilogram, kind_of<isq::absorbed_dose>> {} gray;
+inline constexpr struct sievert : named_unit<"Sv", joule / kilogram, kind_of<isq::dose_equivalent>> {} sievert;
 inline constexpr struct katal : named_unit<"kat", mole / second> {} katal;
 // clang-format on
 
diff --git a/test/unit_test/static/isq_test.cpp b/test/unit_test/static/isq_test.cpp
index f61878de..3eafc09d 100644
--- a/test/unit_test/static/isq_test.cpp
+++ b/test/unit_test/static/isq_test.cpp
@@ -326,4 +326,10 @@ static_assert(verify(isq::reactive_power, scalar, V* A));
 static_assert(verify(isq::non_active_power, scalar, V* A));
 static_assert(verify(isq::active_energy, scalar, J, W* h));
 
+// atomic and nuclear physics
+static_assert(verify(isq::activity, scalar, Bq, 1 / s));
+static_assert(verify(isq::absorbed_dose, scalar, Gy, J / kg, m2 / s2));
+static_assert(verify(isq::quality_factor, scalar, one));
+static_assert(verify(isq::dose_equivalent, scalar, Sv, J / kg, m2 / s2));
+
 }  // namespace