Index: lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/model/AssessmentResult.java
===================================================================
diff -u -r9c3a64b840753192b333afb73c8fe7bdb54be638 -rf280ea4699aa04587b63c0fef3e2a02b7d847c0d
--- lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/model/AssessmentResult.java	(.../AssessmentResult.java)	(revision 9c3a64b840753192b333afb73c8fe7bdb54be638)
+++ lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/model/AssessmentResult.java	(.../AssessmentResult.java)	(revision f280ea4699aa04587b63c0fef3e2a02b7d847c0d)
@@ -20,9 +20,9 @@
  * ****************************************************************
  */
 
-
 package org.lamsfoundation.lams.tool.assessment.model;
 
+import java.time.LocalDateTime;
 import java.util.Date;
 import java.util.Set;
 import java.util.TreeSet;
@@ -53,38 +53,38 @@
     @Column
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long uid;
-    
+
     @Column(name = "start_date")
     private Date startDate;
-    
+
     //date when user has started activity (pressed start button) that has time limitation
     @Column(name = "time_limit_launched_date")
-    private Date timeLimitLaunchedDate;
-    
+    private LocalDateTime timeLimitLaunchedDate;
+
     //indicates the latest retry
     @Column
     private Boolean latest;
-    
+
     @Column(name = "finish_date")
     private Date finishDate;
-    
+
     @Column(name = "session_id")
     private Long sessionId;
-    
+
     @Column(name = "maximum_grade")
     private int maximumGrade;
-    
+
     @Column
     private float grade;
-    
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "assessment_uid")
     private Assessment assessment;
-    
+
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "user_uid")
     private AssessmentUser user;
-    
+
     @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
     @JoinColumn(name = "result_uid")
     private Set<AssessmentQuestionResult> questionResults = new TreeSet<>();
@@ -129,14 +129,14 @@
     public void setStartDate(Date startDate) {
 	this.startDate = startDate;
     }
-    
-   public Date getTimeLimitLaunchedDate() {
+
+    public LocalDateTime getTimeLimitLaunchedDate() {
 	return timeLimitLaunchedDate;
-   }
+    }
 
-   public void setTimeLimitLaunchedDate(Date timeLimitLaunchedDate) {
+    public void setTimeLimitLaunchedDate(LocalDateTime timeLimitLaunchedDate) {
 	this.timeLimitLaunchedDate = timeLimitLaunchedDate;
-   }
+    }
 
     public Boolean isLatest() {
 	return latest;
Index: lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/service/AssessmentServiceImpl.java
===================================================================
diff -u -r36e9121497b2c963250d22ec0f660fd66934182e -rf280ea4699aa04587b63c0fef3e2a02b7d847c0d
--- lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/service/AssessmentServiceImpl.java	(.../AssessmentServiceImpl.java)	(revision 36e9121497b2c963250d22ec0f660fd66934182e)
+++ lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/service/AssessmentServiceImpl.java	(.../AssessmentServiceImpl.java)	(revision f280ea4699aa04587b63c0fef3e2a02b7d847c0d)
@@ -26,6 +26,8 @@
 import java.io.IOException;
 import java.lang.reflect.InvocationTargetException;
 import java.sql.Timestamp;
+import java.time.Duration;
+import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -306,7 +308,7 @@
     @Override
     public void launchTimeLimit(Long assessmentUid, Long userId) {
 	AssessmentResult lastResult = getLastAssessmentResult(assessmentUid, userId);
-	lastResult.setTimeLimitLaunchedDate(new Date());
+	lastResult.setTimeLimitLaunchedDate(LocalDateTime.now());
 	assessmentResultDao.saveObject(lastResult);
     }
 
@@ -318,9 +320,11 @@
 	if (assessment.getTimeLimit() != 0) {
 	    // if user has pressed OK button already - calculate remaining time, and full time otherwise
 	    boolean isTimeLimitNotLaunched = (lastResult == null) || (lastResult.getTimeLimitLaunchedDate() == null);
+
 	    secondsLeft = isTimeLimitNotLaunched ? assessment.getTimeLimit() * 60
 		    : assessment.getTimeLimit() * 60
-			    - (System.currentTimeMillis() - lastResult.getTimeLimitLaunchedDate().getTime()) / 1000;
+			    - Duration.between(lastResult.getTimeLimitLaunchedDate(), LocalDateTime.now()).toSeconds();
+
 	    // change negative or zero number to 1
 	    secondsLeft = Math.max(1, secondsLeft);
 	}
@@ -339,8 +343,7 @@
 
 	//check if the time limit is exceeded
 	return (lastLeaderResult != null) && (lastLeaderResult.getTimeLimitLaunchedDate() != null)
-		&& lastLeaderResult.getTimeLimitLaunchedDate().getTime() + timeLimit * 60000 < System
-			.currentTimeMillis();
+		&& lastLeaderResult.getTimeLimitLaunchedDate().plusSeconds(timeLimit).isBefore(LocalDateTime.now());
     }
 
     @Override