diff --git a/README.md b/README.md
index d521144..8d149e8 100644
--- a/README.md
+++ b/README.md
@@ -249,6 +249,8 @@ run_migration
 | `EXPORTER_CLICKHOUSE_DATABASE` | ❌ | `agile` | Database for exporter CH tables |
 | `EXPORTER_CLICKHOUSE_ISSUES_TABLE` | ❌ | `issues` | Table when store issues metadata |
 | `EXPORTER_CLICKHOUSE_ISSUE_METRICS_TABLE` | ❌ | `issue_metrics` | Table when store issue metrics |
+| `EXPORTER_WORKHOURS_START` | ❌ | 9 | The beginning of working hours for calculating business hour metrics |
+| `EXPORTER_WORKHOURS_END` | ❌ | 22 | The end of working hours for calculating business hour metrics |
 
 
 # Monitoring
diff --git a/tracker_exporter/defaults.py b/tracker_exporter/defaults.py
index 3186af0..a021276 100644
--- a/tracker_exporter/defaults.py
+++ b/tracker_exporter/defaults.py
@@ -6,9 +6,13 @@
 UPLOAD_TO_STORAGE = os.environ.get("EXPORTER_ENABLE_UPLOAD", "false").lower() in ("true", "yes")
 
 # Business days settings
-BUSINESS_HOURS_START = dt.time(9)
-BUSINESS_HOURS_END = dt.time(22)
 WORKDAYS = [0, 1, 2, 3, 4]  # From Monday to Friday
+try:
+    BUSINESS_HOURS_START = dt.time(int(os.environ.get("EXPORTER_WORKHOURS_START", "9")))
+    BUSINESS_HOURS_END = dt.time(int(os.environ.get("EXPORTER_WORKHOURS_END", "22")))
+except (ValueError, TypeError):
+    BUSINESS_HOURS_START = dt.time(9)
+    BUSINESS_HOURS_END = dt.time(22)
 
 # Monitoring settings
 MONITORING_ENABLED = os.environ.get("EXPORTER_MONITORING_ENABLED", "false").lower() in ("true", "yes")