diff --git a/test/test.f90 b/test/test.f90
index f8f2b4b..0b8dca5 100644
--- a/test/test.f90
+++ b/test/test.f90
@@ -1,3 +1,28 @@
 program main
-    print *, "TEST THIS!"
+    use forsus, only: Substance, pr
+    implicit none
+    real(pr) :: tolerance = 1e-4
+    type(Substance) :: sus
+
+    sus = Substance("ethanol")
+
+    call test(6148000._pr, sus%critical%critical_pressure%value, "Pc")
+    call test(513.91999999999996_pr, sus%critical%critical_temperature%value, "Tc")
+    call test(0.167_pr, sus%critical%critical_volume%value, "Vc")
+    call test(0.649_pr, sus%critical%acentric_factor%value, "w")
+
+contains
+    subroutine test(value, calc_value, name)
+        real(pr), intent(in) :: value
+        real(pr), intent(in) :: calc_value
+        character(len=*), intent(in) :: name
+
+        write(*, "(A)", advance="no") name
+        if (abs((value - calc_value)/value) > tolerance) then
+            print *, "Error!"
+            call exit(1)
+        else
+            print *, "Ok!"
+        end if
+    end subroutine
 end program
\ No newline at end of file