diff --git a/docs/src/fortran/lib/constants.rst b/docs/src/fortran/lib/constants.rst
index 6e60df86..0217910d 100644
--- a/docs/src/fortran/lib/constants.rst
+++ b/docs/src/fortran/lib/constants.rst
@@ -39,6 +39,8 @@ View source code :source:`fortran/include/constants.f90`
 
     Denotes the exit codes of different failure modes, counting up from 1
 
+.. f:variable:: DATA_MAX_NAME_SIZE
+    :type: integer
 .. f:variable:: ANSWERT_STR_SIZE
     :type: integer
 
diff --git a/docs/src/fortran/lib/utils.rst b/docs/src/fortran/lib/utils.rst
index 1fca3786..fa9ceb66 100644
--- a/docs/src/fortran/lib/utils.rst
+++ b/docs/src/fortran/lib/utils.rst
@@ -5,6 +5,14 @@ View source code :source:`fortran/include/utils.f90`
 
 .. f:module:: utils
 
+.. f:function:: open_data_file(name)
+
+    Return the unit number for a newly-opened file in ``/_data/``, where ``/`` is the repository root.
+
+    :p character(len=DATA_MAX_NAME_SIZE) id:
+    :returns unit:
+    :rtype unit: integer
+
 .. f:function:: get_answer(id)
 
     Return the answer to a given problem, as represented in ``/_data/answers.tsv``, where ``/`` is the repository root.
diff --git a/fortran/src/include/constants.f90 b/fortran/src/include/constants.f90
index 6a5ec563..4e73d8fa 100644
--- a/fortran/src/include/constants.f90
+++ b/fortran/src/include/constants.f90
@@ -20,6 +20,7 @@ module constants
     integer, parameter :: ERROR_UTILS_ALLOCATE_FAILED = 5
 
     ! file/string sizes
+    integer, parameter :: DATA_MAX_NAME_SIZE = 32
     integer, parameter :: ANSWERT_STR_SIZE = 16
 end module constants
 
diff --git a/fortran/src/include/utils.f90 b/fortran/src/include/utils.f90
index 7192c1b0..8bb44066 100644
--- a/fortran/src/include/utils.f90
+++ b/fortran/src/include/utils.f90
@@ -13,7 +13,7 @@ module utils
     type(AnswerT), private, dimension(1024) :: cached_answers
 contains
     integer function open_data_file(name) result(unit)
-        character(len=32), intent(in) :: name
+        character(len=DATA_MAX_NAME_SIZE), intent(in) :: name
         integer :: ios
 
         unit = prev_unit + 1
@@ -42,7 +42,7 @@ type(AnswerT) function get_answer(id) result(answer)
     end function
 
     subroutine init_answer_cache()
-        character(len=32), parameter ::file_name = "answers.tsv"
+        character(len=DATA_MAX_NAME_SIZE), parameter ::file_name = "answers.tsv"
         character(len=64) :: line
         character(len=32) :: val
         character(len=4) :: id_, type_, length
diff --git a/fortran/src/p0022.f90 b/fortran/src/p0022.f90
index dfd72742..17a6630c 100644
--- a/fortran/src/p0022.f90
+++ b/fortran/src/p0022.f90
@@ -22,6 +22,7 @@ module Problem0022
     integer, parameter :: longest_name = 11
 contains
     integer(i18t) function p0022() result(answer)
+        character(len=DATA_MAX_NAME_SIZE), parameter :: file_name = "p0022_names.txt"
         character(len=longest_name), dimension(name_count) :: names
         character(len=1) current_char
         integer(i18t) score
@@ -30,14 +31,14 @@ integer(i18t) function p0022() result(answer)
         i = 1
         answer = 0
         names = ''
-        unit = open_data_file("p0022_names.txt")
+        unit = open_data_file(file_name)
         do
             read(unit, '(A1)', IOSTAT=ios) current_char
             if (ios /= 0) then
                 exit
             end if
 
-            select case current_char
+            select case (current_char)
                 case (',')
                     i = i + 1
                 case ('"')