diff --git a/core/attributedef/AttributeDuration.php b/core/attributedef/AttributeDuration.php
new file mode 100644
index 000000000..f875f22b7
--- /dev/null
+++ b/core/attributedef/AttributeDuration.php
@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * Store a duration as a number of seconds
+ *
+ * @package     iTopORM
+ */
+class AttributeDuration extends AttributeInteger
+{
+    /**
+     * Useless constructor, but if not present PHP 7.4.0/7.4.1 is crashing :( (N°2329)
+     *
+     * @see https://www.php.net/manual/fr/language.oop5.decon.php states that child constructor can be ommited
+     * @see https://bugs.php.net/bug.php?id=79010 bug solved in PHP 7.4.9
+     *
+     * @param string $sCode
+     * @param array $aParams
+     *
+     * @throws \Exception
+     * @noinspection SenselessProxyMethodInspection
+     */
+    public function __construct($sCode, $aParams)
+    {
+        parent::__construct($sCode, $aParams);
+    }
+
+    public function GetEditClass()
+    {
+        return "Duration";
+    }
+
+    protected function GetSQLCol($bFullSpec = false)
+    {
+        return "INT(11) UNSIGNED";
+    }
+
+    public function GetNullValue()
+    {
+        return '0';
+    }
+
+    public function MakeRealValue($proposedValue, $oHostObj)
+    {
+        if (is_null($proposedValue)) {
+            return null;
+        }
+        if (!is_numeric($proposedValue)) {
+            return null;
+        }
+        if (((int)$proposedValue) < 0) {
+            return null;
+        }
+
+        return (int)$proposedValue;
+    }
+
+    public function ScalarToSQL($value)
+    {
+        if (is_null($value)) {
+            return null;
+        }
+
+        return $value;
+    }
+
+    public function GetAsHTML($value, $oHostObject = null, $bLocalize = true)
+    {
+        return Str::pure2html(self::FormatDuration($value));
+    }
+
+    public static function FormatDuration($duration)
+    {
+        $aDuration = self::SplitDuration($duration);
+
+        if ($duration < 60) {
+            // Less than 1 min
+            $sResult = Dict::Format('Core:Duration_Seconds', $aDuration['seconds']);
+        } else {
+            if ($duration < 3600) {
+                // less than 1 hour, display it in minutes/seconds
+                $sResult = Dict::Format('Core:Duration_Minutes_Seconds', $aDuration['minutes'], $aDuration['seconds']);
+            } else {
+                if ($duration < 86400) {
+                    // Less than 1 day, display it in hours/minutes/seconds
+                    $sResult = Dict::Format('Core:Duration_Hours_Minutes_Seconds', $aDuration['hours'],
+                        $aDuration['minutes'], $aDuration['seconds']);
+                } else {
+                    // more than 1 day, display it in days/hours/minutes/seconds
+                    $sResult = Dict::Format('Core:Duration_Days_Hours_Minutes_Seconds', $aDuration['days'],
+                        $aDuration['hours'], $aDuration['minutes'], $aDuration['seconds']);
+                }
+            }
+        }
+
+        return $sResult;
+    }
+
+    static function SplitDuration($duration)
+    {
+        $duration = (int)$duration;
+        $days = floor($duration / 86400);
+        $hours = floor(($duration - (86400 * $days)) / 3600);
+        $minutes = floor(($duration - (86400 * $days + 3600 * $hours)) / 60);
+        $seconds = ($duration % 60); // modulo
+
+        return array('days' => $days, 'hours' => $hours, 'minutes' => $minutes, 'seconds' => $seconds);
+    }
+
+    public static function GetFormFieldClass()
+    {
+        return '\\Combodo\\iTop\\Form\\Field\\DurationField';
+    }
+
+    public function MakeFormField(DBObject $oObject, $oFormField = null)
+    {
+        if ($oFormField === null) {
+            $sFormFieldClass = static::GetFormFieldClass();
+            $oFormField = new $sFormFieldClass($this->GetCode());
+        }
+        parent::MakeFormField($oObject, $oFormField);
+
+        // Note : As of today, this attribute is -by nature- only supported in readonly mode, not edition
+        $sAttCode = $this->GetCode();
+        $oFormField->SetCurrentValue($oObject->Get($sAttCode));
+        $oFormField->SetReadOnly(true);
+
+        return $oFormField;
+    }
+
+}
\ No newline at end of file