diff --git a/app/common/rational.cpp b/app/common/rational.cpp
index 34d627572..e7020f92b 100644
--- a/app/common/rational.cpp
+++ b/app/common/rational.cpp
@@ -186,6 +186,8 @@ const rational& rational::operator=(const rational &rhs)
 
 const rational& rational::operator+=(const rational &rhs)
 {
+  Q_ASSERT(*this != RATIONAL_MIN && *this != RATIONAL_MAX && rhs != RATIONAL_MIN && rhs != RATIONAL_MAX);
+
   if (!isNaN()) {
     if (rhs.isNaN()) {
       // Set to NaN
@@ -209,6 +211,8 @@ const rational& rational::operator+=(const rational &rhs)
 
 const rational& rational::operator-=(const rational &rhs)
 {
+  Q_ASSERT(*this != RATIONAL_MIN && *this != RATIONAL_MAX && rhs != RATIONAL_MIN && rhs != RATIONAL_MAX);
+
   if (!isNaN()) {
     if (rhs.isNaN()) {
       // Set to NaN
@@ -232,6 +236,8 @@ const rational& rational::operator-=(const rational &rhs)
 
 const rational& rational::operator/=(const rational &rhs)
 {
+  Q_ASSERT(*this != RATIONAL_MIN && *this != RATIONAL_MAX && rhs != RATIONAL_MIN && rhs != RATIONAL_MAX);
+
   if (!isNaN()) {
     if (rhs.isNaN()) {
       // Set to NaN
@@ -250,6 +256,8 @@ const rational& rational::operator/=(const rational &rhs)
 
 const rational& rational::operator*=(const rational &rhs)
 {
+  Q_ASSERT(*this != RATIONAL_MIN && *this != RATIONAL_MAX && rhs != RATIONAL_MIN && rhs != RATIONAL_MAX);
+
   if (!isNaN()) {
     if (rhs.isNaN()) {
       denom_ = 0;
diff --git a/app/common/rational.h b/app/common/rational.h
index 074f1b864..26f625fc6 100644
--- a/app/common/rational.h
+++ b/app/common/rational.h
@@ -1,7 +1,7 @@
 //Copyright 2015 Adam Quintero
 //This program is distributed under the terms of the GNU General Public License.
 
-// Adapted by MattKC for the Olive Video Editor (2019)
+// Adapted by MattKC for the Olive Video Editor (2019-2022)
 
 #ifndef RATIONAL_H
 #define RATIONAL_H
diff --git a/app/common/timerange.cpp b/app/common/timerange.cpp
index c352e476d..c4337a7aa 100644
--- a/app/common/timerange.cpp
+++ b/app/common/timerange.cpp
@@ -44,6 +44,7 @@ const rational &TimeRange::out() const
 
 const rational &TimeRange::length() const
 {
+  Q_ASSERT(!length_.isNaN());
   return length_;
 }
 
@@ -173,7 +174,11 @@ void TimeRange::normalize()
   }
 
   // Calculate length
-  length_ = out_ - in_;
+  if (out_ == RATIONAL_MIN || out_ == RATIONAL_MAX || in_ == RATIONAL_MIN || in_ == RATIONAL_MAX) {
+    length_ = rational::NaN;
+  } else {
+    length_ = out_ - in_;
+  }
 }
 
 void TimeRangeList::insert(const TimeRangeList &list_to_add)