diff --git a/CRM/CivirulesConditions/AgeComparison.php b/CRM/CivirulesConditions/AgeComparison.php
index 31bebc248aef5ac876497c28382c8b7d83a1a1c5..e7808b3827ecd0358ceef19320b8437cdeb1ac8c 100644
--- a/CRM/CivirulesConditions/AgeComparison.php
+++ b/CRM/CivirulesConditions/AgeComparison.php
@@ -1,27 +1,35 @@
 <?php
+/**
+ * Class for CiviRules AgeComparison (extending generic ValueComparison)
+ *
+ * @author Jaap Jansma (CiviCooP) <jaap.jansma@civicoop.org>
+ * @license AGPL-3.0
+ */
 
 class CRM_CivirulesConditions_AgeComparison extends CRM_CivirulesConditions_Generic_ValueComparison {
 
   /**
    * Returns value of the field
    *
-   * @param CRM_Civirules_EventData_EventData $eventData
+   * @param object CRM_Civirules_EventData_EventData $eventData
    * @return mixed
+   * @access protected
    */
   protected function getFieldValue(CRM_Civirules_EventData_EventData $eventData) {
-    $birth_date = civicrm_api3('Contact', 'getvalue', array('id' => $eventData->getContactId(), 'return' => 'birth_date'));
-    if ($birth_date) {
-      $birthDate = new DateTime($birth_date);
+    $sourceBirthDate = civicrm_api3('Contact', 'getvalue', array('id' => $eventData->getContactId(), 'return' => 'birth_date'));
+    if ($sourceBirthDate) {
+      $birthDate = new DateTime($sourceBirthDate);
       return $birthDate->diff(new DateTime('now'))->y;
     }
     return false; //undefined birth date
   }
 
   /**
-   * Retruns a user friendly text explaining the condition params
+   * Returns a user friendly text explaining the condition params
    * e.g. 'Older than 65'
    *
    * @return string
+   * @access public
    */
   public function userFriendlyConditionParams() {
     switch ($this->getOperator()) {
@@ -54,6 +62,7 @@ class CRM_CivirulesConditions_AgeComparison extends CRM_CivirulesConditions_Gene
    * Returns an array with required entity names
    *
    * @return array
+   * @access public
    */
   public function requiredEntities() {
     return array('contact');
diff --git a/CRM/CivirulesConditions/BirthdayChanged.php b/CRM/CivirulesConditions/BirthdayChanged.php
index 99e2605936384583258c98a7ad119b02a05f8797..a67f363db3dc4346a1f242cca61633fa4d64864d 100644
--- a/CRM/CivirulesConditions/BirthdayChanged.php
+++ b/CRM/CivirulesConditions/BirthdayChanged.php
@@ -1,4 +1,10 @@
 <?php
+/**
+ * Class for CiviRules AgeComparison (extending generic ValueComparison)
+ *
+ * @author Jaap Jansma (CiviCooP) <jaap.jansma@civicoop.org>
+ * @license AGPL-3.0
+ */
 
 class CRM_CivirulesConditions_BirthdayChanged extends CRM_CivirulesConditions_Generic_FieldChanged {
 
@@ -6,6 +12,7 @@ class CRM_CivirulesConditions_BirthdayChanged extends CRM_CivirulesConditions_Ge
    * Returns name of entity
    *
    * @return string
+   * @access protected
    */
   protected function getEntity() {
     return 'contact';
@@ -13,14 +20,16 @@ class CRM_CivirulesConditions_BirthdayChanged extends CRM_CivirulesConditions_Ge
 
   /**
    * Returns name of the field
+   *
    * @return string
+   * @access protected
    */
   protected function getField() {
     return 'birth_date';
   }
 
   /**
-   * This function could be overridden in subclasses to
+   * This method could be overridden in subclasses to
    * transform field data to a certain type
    *
    * E.g. a date field could be transformed to a DataTime object so that
@@ -28,6 +37,7 @@ class CRM_CivirulesConditions_BirthdayChanged extends CRM_CivirulesConditions_Ge
    *
    * @param $fieldData
    * @return mixed
+   * @access protected
    */
   protected function transformFieldData($fieldData) {
     return new DateTime($fieldData);
diff --git a/CRM/CivirulesConditions/PrimaryEmailChanged.php b/CRM/CivirulesConditions/PrimaryEmailChanged.php
index 737b77d50ef4f21b3a046004c65dd85f7ef6d055..78b92478030256756244c3e70ca727f2903aceed 100644
--- a/CRM/CivirulesConditions/PrimaryEmailChanged.php
+++ b/CRM/CivirulesConditions/PrimaryEmailChanged.php
@@ -1,4 +1,10 @@
 <?php
+/**
+ * Class for CiviRules Primary Email Changed condition (extending generic FieldChanged)
+ *
+ * @author Jaap Jansma (CiviCooP) <jaap.jansma@civicoop.org>
+ * @license AGPL-3.0
+ */
 
 class CRM_CivirulesConditions_PrimaryEmailChanged extends CRM_CivirulesConditions_Generic_FieldChanged {
 
@@ -6,6 +12,7 @@ class CRM_CivirulesConditions_PrimaryEmailChanged extends CRM_CivirulesCondition
    * Returns name of entity
    *
    * @return string
+   * @access protected
    */
   protected function getEntity() {
     return 'Email';
@@ -13,13 +20,21 @@ class CRM_CivirulesConditions_PrimaryEmailChanged extends CRM_CivirulesCondition
 
   /**
    * Returns name of the field
+   *
    * @return string
+   * @access protected
    */
   protected function getField() {
     return 'email';
   }
 
-
+  /**
+   * Method to check if the condition is valid
+   *
+   * @param object CRM_Civirules_EventData_EventData $eventData
+   * @return bool
+   * @access public
+   */
   public function isConditionValid(CRM_Civirules_EventData_EventData $eventData) {
     $isValid = parent::isConditionValid($eventData);
     if ($isValid) {
@@ -32,5 +47,4 @@ class CRM_CivirulesConditions_PrimaryEmailChanged extends CRM_CivirulesCondition
     }
     return $isValid;
   }
-
 }
\ No newline at end of file
diff --git a/CRM/CivirulesCronEvent/Birthday.php b/CRM/CivirulesCronEvent/Birthday.php
index 317c635faf8fb3a27fc0d7319891380fb1cd8c60..724f9b88835ea6413159737f68eabbc3dabb748f 100644
--- a/CRM/CivirulesCronEvent/Birthday.php
+++ b/CRM/CivirulesCronEvent/Birthday.php
@@ -1,15 +1,22 @@
 <?php
+/**
+ * Class for CiviRules CronEvent Birthday
+ *
+ * @author Jaap Jansma (CiviCooP) <jaap.jansma@civicoop.org>
+ * @license AGPL-3.0
+ */
 
 class CRM_CivirulesCronEvent_Birthday extends CRM_Civirules_Event_Cron {
 
   private $dao = false;
 
   /**
-   * This function returns a CRM_Civirules_EventData_EventData this entity is used for triggering the rule
+   * This method returns a CRM_Civirules_EventData_EventData this entity is used for triggering the rule
    *
    * Return false when no next entity is available
    *
-   * @return CRM_Civirules_EventData_EventData|false
+   * @return object|bool CRM_Civirules_EventData_EventData|false
+   * @access protected
    */
   protected function getNextEntityEventData() {
     if (!$this->dao) {
@@ -24,6 +31,11 @@ class CRM_CivirulesCronEvent_Birthday extends CRM_Civirules_Event_Cron {
     return false;
   }
 
+  /**
+   * Method to query event entities
+   *
+   * @access private
+   */
   private function queryForEventEntities() {
     $sql = "SELECT c.*
             FROM `civicrm_contact` `c`