diff --git a/rct229/utils/std_comparisons_test.py b/rct229/utils/std_comparisons_test.py
index 7d87069a54..9213d170f1 100644
--- a/rct229/utils/std_comparisons_test.py
+++ b/rct229/utils/std_comparisons_test.py
@@ -13,6 +13,7 @@
 )
 
 _M2 = ureg("m2")
+_TONS = ureg("tons")
 
 
 def test__std_equal__true_with_units():
@@ -194,6 +195,10 @@ def test__std_equal_with_precision__10_false_without_units():
     assert not std_equal_with_precision(155, 150, 10)
 
 
+def test__std_equal_with_precision__1_true_with_units():
+    assert std_equal_with_precision(19.47 * _TONS, 19.52 * _TONS, 1 * _TONS)
+
+
 def test__std_conservative_outcome__true_with_units_gt():
     assert std_conservative_outcome(1.1 * _M2, 1.05 * _M2, operator.gt)