diff --git a/documentation/RELEASE_NOTES.html b/documentation/RELEASE_NOTES.html
index d2d32e559..a901b5190 100644
--- a/documentation/RELEASE_NOTES.html
+++ b/documentation/RELEASE_NOTES.html
@@ -14,6 +14,14 @@
 <h2 align="center">Changes between 3.15.1 and 3.15.2</h2>
 <!-- Insert new items immediately below here ... -->
 
+<h3>aoRecord raw conversion overflows</h3>
+
+<p>The ao record type now checks converted raw values and limits them to the
+32-bit integer range before writing them to the RVAL field. Previously value
+overflows relied on Undefined Behaviour which could give different results on
+different platforms. The ROFF fields of the ao and ai record types are now
+DBF_ULONG to allow an ROFF setting of 0x80000000 to work properly.</p>
+
 <h3>Changes to &lt;top&gt;/cfg/* files</h3>
 
 <p>The order in which cfg/CONFIG* and cfg/RULES* files are included from support
diff --git a/src/ca/client/tools/tool_lib.c b/src/ca/client/tools/tool_lib.c
index 8b9c5ca28..db670151a 100644
--- a/src/ca/client/tools/tool_lib.c
+++ b/src/ca/client/tools/tool_lib.c
@@ -85,7 +85,8 @@ static void sprint_long (char *ret, dbr_long_t val, IntFormatT outType)
             "0x%lX" /* hex */
         };
 
-        sprintf(ret, fmt[outType], val);
+        /* Formats have long modifier, pass value as a long */
+        sprintf(ret, fmt[outType], (long) val);
     }
 }
 
diff --git a/src/std/rec/aiRecord.dbd.pod b/src/std/rec/aiRecord.dbd.pod
index e3f1cfdae..8da77055d 100644
--- a/src/std/rec/aiRecord.dbd.pod
+++ b/src/std/rec/aiRecord.dbd.pod
@@ -404,8 +404,8 @@ monitoring functionality.
         pp(TRUE)
         interest(2)
     }
-    field(ROFF,DBF_LONG) {
-        prompt("Raw Offset, obsolete")
+    field(ROFF,DBF_ULONG) {
+        prompt("Raw Offset")
         pp(TRUE)
         interest(2)
     }
diff --git a/src/std/rec/aoRecord.c b/src/std/rec/aoRecord.c
index a3def5607..63125593e 100644
--- a/src/std/rec/aoRecord.c
+++ b/src/std/rec/aoRecord.c
@@ -498,10 +498,20 @@ static void convert(aoRecord *prec, double value)
     }
     value -= prec->aoff;
     if (prec->aslo != 0) value /= prec->aslo;
-    if (value >= 0.0)
-        prec->rval = (epicsInt32)(value + 0.5) - prec->roff;
-    else
-        prec->rval = (epicsInt32)(value - 0.5) - prec->roff;
+
+    /* Apply raw offset and limits, round to 32-bit integer */
+    value -= prec->roff;
+    if (value >= 0.0) {
+        if (value >= (0x7fffffff - 0.5))
+            prec->rval = 0x7fffffff;
+        else
+            prec->rval = (epicsInt32)(value + 0.5);
+    } else {
+        if (value > (0.5 - 0x80000000))
+            prec->rval = (epicsInt32)(value - 0.5);
+        else
+            prec->rval = 0x80000000;
+    }
 }
 
 
diff --git a/src/std/rec/aoRecord.dbd.pod b/src/std/rec/aoRecord.dbd.pod
index 27e156ae1..5b9280a65 100644
--- a/src/std/rec/aoRecord.dbd.pod
+++ b/src/std/rec/aoRecord.dbd.pod
@@ -342,8 +342,8 @@ information on these fields.
         size(16)
 		prop(YES)
     }
-    field(ROFF,DBF_LONG) {
-        prompt("Raw Offset, obsolete")
+    field(ROFF,DBF_ULONG) {
+        prompt("Raw Offset")
         pp(TRUE)
         interest(2)
     }