diff --git a/lib/activity_notification/orm/active_record/notification.rb b/lib/activity_notification/orm/active_record/notification.rb
index ba73b52..68596bd 100644
--- a/lib/activity_notification/orm/active_record/notification.rb
+++ b/lib/activity_notification/orm/active_record/notification.rb
@@ -45,11 +45,13 @@ class Notification < ::ActiveRecord::Base
         belongs_to :notifier,      polymorphic: true, optional: true
 
         # Serialize parameters Hash
+        # :nocov:
         if Rails.gem_version >= Gem::Version.new('7.1')
           serialize  :parameters, type: Hash, coder: YAML
         else
           serialize  :parameters, Hash
         end
+        # :nocov:
 
         validates  :target,        presence: true
         validates  :notifiable,    presence: true
diff --git a/lib/activity_notification/orm/active_record/subscription.rb b/lib/activity_notification/orm/active_record/subscription.rb
index efa0ff4..72046fb 100644
--- a/lib/activity_notification/orm/active_record/subscription.rb
+++ b/lib/activity_notification/orm/active_record/subscription.rb
@@ -14,11 +14,13 @@ class Subscription < ::ActiveRecord::Base
         belongs_to :target,               polymorphic: true
 
         # Serialize parameters Hash
+        # :nocov:
         if Rails.gem_version >= Gem::Version.new('7.1')
           serialize  :optional_targets, type: Hash, coder: YAML
         else
           serialize  :optional_targets, Hash
         end
+        # :nocov:
 
         validates  :target,               presence: true
         validates  :key,                  presence: true, uniqueness: { scope: :target }