diff --git a/actionpack/lib/action_view/helpers/number_helper.rb b/actionpack/lib/action_view/helpers/number_helper.rb
index 77f19b3..6dff90c 100644
--- a/actionpack/lib/action_view/helpers/number_helper.rb
+++ b/actionpack/lib/action_view/helpers/number_helper.rb
@@ -220,7 +220,6 @@ module ActionView
         end
       end
 
-      STORAGE_UNITS = %w( Bytes KB MB GB TB ).freeze
 
       # Formats the bytes in +size+ into a more understandable representation
       # (e.g., giving it 1500 yields 1.5 KB). This method is useful for
@@ -253,7 +252,8 @@ module ActionView
 
         options = args.extract_options!
         options.symbolize_keys!
-
+        
+        storage_units = I18n.translate(:'number.human.format.storage_units', :locale => options[:locale], :raise => true) rescue %w( Bytes KB MB GB TB PB )
         defaults = I18n.translate(:'number.format', :locale => options[:locale], :raise => true) rescue {}
         human    = I18n.translate(:'number.human.format', :locale => options[:locale], :raise => true) rescue {}
         defaults = defaults.merge(human)
@@ -264,16 +264,16 @@ module ActionView
           precision = args[0] || defaults[:precision]
         end
 
-        precision ||= (options[:precision] || defaults[:precision])
-        separator ||= (options[:separator] || defaults[:separator])
-        delimiter ||= (options[:delimiter] || defaults[:delimiter])
+        precision ||= (options[:precision] || defaults[:precision] || 1)
+        separator ||= (options[:separator] || defaults[:separator] || "")
+        delimiter ||= (options[:delimiter] || defaults[:delimiter] || "")
 
-        max_exp  = STORAGE_UNITS.size - 1
+        max_exp  = storage_units.size - 1
         number   = Float(number)
         exponent = (Math.log(number) / Math.log(1024)).to_i # Convert to base 1024
         exponent = max_exp if exponent > max_exp # we need this to avoid overflow for the highest unit
         number  /= 1024 ** exponent
-        unit     = STORAGE_UNITS[exponent]
+        unit     = storage_units[exponent]
 
         begin
           escaped_separator = Regexp.escape(separator)