diff --git a/libreplan-webapp/src/main/java/org/libreplan/importers/ExportTimesheetsToTim.java b/libreplan-webapp/src/main/java/org/libreplan/importers/ExportTimesheetsToTim.java
index 9bdbb3ad0..c4e7a7c60 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/importers/ExportTimesheetsToTim.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/importers/ExportTimesheetsToTim.java
@@ -32,6 +32,7 @@ import org.libreplan.business.common.IAdHocTransactionService;
 import org.libreplan.business.common.IOnTransaction;
 import org.libreplan.business.common.daos.IAppPropertiesDAO;
 import org.libreplan.business.common.daos.IConfigurationDAO;
+import org.libreplan.business.common.exceptions.InstanceNotFoundException;
 import org.libreplan.business.orders.daos.IOrderDAO;
 import org.libreplan.business.orders.daos.IOrderSyncInfoDAO;
 import org.libreplan.business.orders.entities.Order;
@@ -81,8 +82,6 @@ public class ExportTimesheetsToTim implements IExportTimesheetsToTim {
     @Autowired
     private IAdHocTransactionService adHocTransactionService;
 
-    private List<Worker> workers;
-
     @Autowired
     private IAppPropertiesDAO appPropertiesDAO;
 
@@ -138,12 +137,6 @@ public class ExportTimesheetsToTim implements IExportTimesheetsToTim {
     private boolean exportTimesheets(String productCode, Order order,
             Map<String, String> appProperties) {
 
-        workers = workerDAO.findAll();
-        if (workers == null || workers.isEmpty()) {
-            LOG.warn("No workers found!");
-            return false;
-        }
-
         String url = appProperties.get("Server");
         String userName = appProperties.get("Username");
         String password = appProperties.get("Password");
@@ -240,9 +233,12 @@ public class ExportTimesheetsToTim implements IExportTimesheetsToTim {
      */
     private TimeRegistrationDTO createExportTimeRegistration(String productCode,
             WorkReportLine workReportLine) {
-        Worker worker = getWorker(workReportLine.getResource().getCode());
-        if (worker == null) {
-            LOG.warn("Worker not found!");
+        Worker worker;
+        String workerCode = workReportLine.getResource().getCode();
+        try {
+            worker = workerDAO.findByCode(workerCode);
+        } catch (InstanceNotFoundException e) {
+            LOG.warn("Worker \"" + workerCode + "\" not found!");
             return null;
         }
 
@@ -271,21 +267,6 @@ public class ExportTimesheetsToTim implements IExportTimesheetsToTim {
         return timeRegistrationDTO;
     }
 
-    /**
-     * get worker based on the specified <code>code</code>
-     *
-     * @param code
-     * @return worker
-     */
-    private Worker getWorker(String code) {
-        for (Worker worker : workers) {
-            if (worker.getCode().equals(code)) {
-                return worker;
-            }
-        }
-        return null;
-    }
-
     @Override
     @Transactional(readOnly = true)
     public OrderSyncInfo getOrderLastSyncInfo(Order order) {
diff --git a/libreplan-webapp/src/main/java/org/libreplan/importers/ImportRosterFromTim.java b/libreplan-webapp/src/main/java/org/libreplan/importers/ImportRosterFromTim.java
index 1e151041f..acf149a71 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/importers/ImportRosterFromTim.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/importers/ImportRosterFromTim.java
@@ -99,8 +99,6 @@ public class ImportRosterFromTim implements IImportRosterFromTim {
     @Qualifier("subclass")
     private IBaseCalendarModel baseCalendarModel;
 
-    private List<Worker> workers;
-
     @Override
     @Transactional
     public void importRosters() {
@@ -133,7 +131,6 @@ public class ImportRosterFromTim implements IImportRosterFromTim {
 
                     @Override
                     public Void execute() {
-                        addAllWorkers();
                         List<RosterException> rosterExceptions = getRosterExceptions(rosterResponse);
                         if (!rosterExceptions.isEmpty()) {
                             updateCalendarException(rosterExceptions);
@@ -159,7 +156,13 @@ public class ImportRosterFromTim implements IImportRosterFromTim {
         List<RosterException> rosterExceptions = new ArrayList<RosterException>();
 
         for (Map.Entry<String, List<RosterDTO>> entry : map.entrySet()) {
-            Worker worker = getWorker(entry.getKey());
+            Worker worker = null;
+            String workerCode = entry.getKey();
+            try {
+                worker = workerDAO.findByCode(workerCode);
+            } catch (InstanceNotFoundException e) {
+                LOG.warn("Worker \"" + workerCode + "\" not found!");
+            }
             if (worker != null) {
                 List<RosterDTO> list = entry.getValue();
                 Collections.sort(list, new Comparator<RosterDTO>() {
@@ -288,29 +291,6 @@ public class ImportRosterFromTim implements IImportRosterFromTim {
     }
 
 
-    /**
-     * adds all existing workers to workers list
-     */
-    private void addAllWorkers() {
-        workers = workerDAO.findAll();
-    }
-
-    /**
-     * returns {@link Worker} for the specified <code>nif</code>
-     *
-     * @param nif
-     *            the worker's nif
-     * @return Worker if found, otherwise null
-     */
-    private Worker getWorker(String nif) {
-        for (Worker worker : workers) {
-            if (worker.getNif().equals(nif)) {
-                return worker;
-            }
-        }
-        return null;
-    }
-
     /**
      * creates and returns {@link RosterRequestDTO}
      *