diff --git a/test/unit_test/static/quantity_spec_test.cpp b/test/unit_test/static/quantity_spec_test.cpp
index 6cca5e4f..a48db799 100644
--- a/test/unit_test/static/quantity_spec_test.cpp
+++ b/test/unit_test/static/quantity_spec_test.cpp
@@ -87,105 +87,105 @@ QUANTITY_SPEC_(kinetic_energy, mechanical_energy, mass* pow<2>(speed));
 
 // concepts verification
 static_assert(QuantitySpec<length_>);
-static_assert(BaseQuantitySpec<length_>);
+static_assert(detail::BaseQuantitySpec<length_>);
 static_assert(detail::NamedQuantitySpec<length_>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<length_>);
-static_assert(!QuantityKindSpec<length_>);
+static_assert(!detail::QuantityKindSpec<length_>);
 
 static_assert(QuantitySpec<frequency_>);
-static_assert(!BaseQuantitySpec<frequency_>);
+static_assert(!detail::BaseQuantitySpec<frequency_>);
 static_assert(detail::NamedQuantitySpec<frequency_>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<frequency_>);
-static_assert(!QuantityKindSpec<frequency_>);
+static_assert(!detail::QuantityKindSpec<frequency_>);
 
 static_assert(QuantitySpec<decltype(1 / time)>);
-static_assert(!BaseQuantitySpec<decltype(1 / time)>);
+static_assert(!detail::BaseQuantitySpec<decltype(1 / time)>);
 static_assert(!detail::NamedQuantitySpec<decltype(1 / time)>);
 static_assert(detail::IntermediateDerivedQuantitySpec<decltype(1 / time)>);
-static_assert(!QuantityKindSpec<decltype(1 / time)>);
+static_assert(!detail::QuantityKindSpec<decltype(1 / time)>);
 
 static_assert(QuantitySpec<dimensionless_>);
-static_assert(!BaseQuantitySpec<dimensionless_>);
+static_assert(!detail::BaseQuantitySpec<dimensionless_>);
 static_assert(detail::NamedQuantitySpec<dimensionless_>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<dimensionless_>);
-static_assert(!QuantityKindSpec<dimensionless_>);
+static_assert(!detail::QuantityKindSpec<dimensionless_>);
 
 static_assert(QuantitySpec<kind_of_<length>>);
-static_assert(BaseQuantitySpec<kind_of_<length>>);
-static_assert(detail::NamedQuantitySpec<kind_of_<length>>);
+static_assert(!detail::BaseQuantitySpec<kind_of_<length>>);
+static_assert(!detail::NamedQuantitySpec<kind_of_<length>>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<kind_of_<length>>);
-static_assert(QuantityKindSpec<kind_of_<length>>);
+static_assert(detail::QuantityKindSpec<kind_of_<length>>);
 
 static_assert(QuantitySpec<frequency_>);
-static_assert(!BaseQuantitySpec<frequency_>);
+static_assert(!detail::BaseQuantitySpec<frequency_>);
 static_assert(detail::NamedQuantitySpec<frequency_>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<frequency_>);
-static_assert(!QuantityKindSpec<frequency_>);
+static_assert(!detail::QuantityKindSpec<frequency_>);
 
 static_assert(QuantitySpec<decltype(1 / time)>);
-static_assert(!BaseQuantitySpec<decltype(1 / time)>);
+static_assert(!detail::BaseQuantitySpec<decltype(1 / time)>);
 static_assert(!detail::NamedQuantitySpec<decltype(1 / time)>);
 static_assert(detail::IntermediateDerivedQuantitySpec<decltype(1 / time)>);
-static_assert(!QuantityKindSpec<decltype(1 / time)>);
+static_assert(!detail::QuantityKindSpec<decltype(1 / time)>);
 
 static_assert(QuantitySpec<decltype(kind_of<length> / kind_of<time>)>);
-static_assert(!BaseQuantitySpec<decltype(kind_of<length> / kind_of<time>)>);
-static_assert(detail::NamedQuantitySpec<decltype(kind_of<length> / kind_of<time>)>);
+static_assert(!detail::BaseQuantitySpec<decltype(kind_of<length> / kind_of<time>)>);
+static_assert(!detail::NamedQuantitySpec<decltype(kind_of<length> / kind_of<time>)>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<decltype(kind_of<length> / kind_of<time>)>);
-static_assert(QuantityKindSpec<decltype(kind_of<length> / kind_of<time>)>);
+static_assert(detail::QuantityKindSpec<decltype(kind_of<length> / kind_of<time>)>);
 
 static_assert(QuantitySpec<decltype(kind_of<length> * kind_of<time>)>);
-static_assert(!BaseQuantitySpec<decltype(kind_of<length> * kind_of<time>)>);
-static_assert(detail::NamedQuantitySpec<decltype(kind_of<length> * kind_of<time>)>);
+static_assert(!detail::BaseQuantitySpec<decltype(kind_of<length> * kind_of<time>)>);
+static_assert(!detail::NamedQuantitySpec<decltype(kind_of<length> * kind_of<time>)>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<decltype(kind_of<length> * kind_of<time>)>);
-static_assert(QuantityKindSpec<decltype(kind_of<length> * kind_of<time>)>);
+static_assert(detail::QuantityKindSpec<decltype(kind_of<length> * kind_of<time>)>);
 
 // dimensionless
 static_assert(QuantitySpec<dimensionless_>);
-static_assert(!BaseQuantitySpec<dimensionless_>);
+static_assert(!detail::BaseQuantitySpec<dimensionless_>);
 static_assert(detail::NamedQuantitySpec<dimensionless_>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<dimensionless_>);
-static_assert(!QuantityKindSpec<dimensionless_>);
+static_assert(!detail::QuantityKindSpec<dimensionless_>);
 
 static_assert(QuantitySpec<decltype(length / length)>);
-static_assert(!BaseQuantitySpec<decltype(length / length)>);
+static_assert(!detail::BaseQuantitySpec<decltype(length / length)>);
 static_assert(detail::NamedQuantitySpec<decltype(length / length)>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<decltype(length / length)>);
-static_assert(!QuantityKindSpec<decltype(length / length)>);
+static_assert(!detail::QuantityKindSpec<decltype(length / length)>);
 
 static_assert(QuantitySpec<decltype(width / length)>);
-static_assert(!BaseQuantitySpec<decltype(width / length)>);
+static_assert(!detail::BaseQuantitySpec<decltype(width / length)>);
 static_assert(!detail::NamedQuantitySpec<decltype(width / length)>);
 static_assert(detail::IntermediateDerivedQuantitySpec<decltype(width / length)>);
-static_assert(!QuantityKindSpec<decltype(width / length)>);
+static_assert(!detail::QuantityKindSpec<decltype(width / length)>);
 
 static_assert(QuantitySpec<decltype(kind_of<length> / kind_of<length>)>);
-static_assert(!BaseQuantitySpec<decltype(kind_of<length> / kind_of<length>)>);
-static_assert(detail::NamedQuantitySpec<decltype(kind_of<length> / kind_of<length>)>);
+static_assert(!detail::BaseQuantitySpec<decltype(kind_of<length> / kind_of<length>)>);
+static_assert(!detail::NamedQuantitySpec<decltype(kind_of<length> / kind_of<length>)>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<decltype(kind_of<length> / kind_of<length>)>);
-static_assert(QuantityKindSpec<decltype(kind_of<length> / kind_of<length>)>);
+static_assert(detail::QuantityKindSpec<decltype(kind_of<length> / kind_of<length>)>);
 
 static_assert(QuantitySpec<decltype(kind_of<length> / length)>);
-static_assert(!BaseQuantitySpec<decltype(kind_of<length> / length)>);
+static_assert(!detail::BaseQuantitySpec<decltype(kind_of<length> / length)>);
 static_assert(detail::NamedQuantitySpec<decltype(kind_of<length> / length)>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<decltype(kind_of<length> / length)>);
-static_assert(!QuantityKindSpec<decltype(kind_of<length> / length)>);
+static_assert(!detail::QuantityKindSpec<decltype(kind_of<length> / length)>);
 
 static_assert(QuantitySpec<decltype(length / kind_of<length>)>);
-static_assert(!BaseQuantitySpec<decltype(length / kind_of<length>)>);
+static_assert(!detail::BaseQuantitySpec<decltype(length / kind_of<length>)>);
 static_assert(detail::NamedQuantitySpec<decltype(length / kind_of<length>)>);
 static_assert(!detail::IntermediateDerivedQuantitySpec<decltype(length / kind_of<length>)>);
-static_assert(!QuantityKindSpec<decltype(length / kind_of<length>)>);
+static_assert(!detail::QuantityKindSpec<decltype(length / kind_of<length>)>);
 
 static_assert(QuantitySpec<decltype(width / kind_of<length>)>);
-static_assert(!BaseQuantitySpec<decltype(width / kind_of<length>)>);
+static_assert(!detail::BaseQuantitySpec<decltype(width / kind_of<length>)>);
 static_assert(!detail::NamedQuantitySpec<decltype(width / kind_of<length>)>);
 static_assert(detail::IntermediateDerivedQuantitySpec<decltype(width / kind_of<length>)>);
-static_assert(!QuantityKindSpec<decltype(width / kind_of<length>)>);
+static_assert(!detail::QuantityKindSpec<decltype(width / kind_of<length>)>);
 
 // length
 static_assert(QuantitySpec<decltype(speed * time)>);
-static_assert(!BaseQuantitySpec<decltype(speed * time)>);
+static_assert(!detail::BaseQuantitySpec<decltype(speed * time)>);
 static_assert(!detail::NamedQuantitySpec<decltype(speed * time)>);
 static_assert(detail::IntermediateDerivedQuantitySpec<decltype(speed * time)>);