diff --git a/symptom_ex_process/symptom_ex_process.tex b/symptom_ex_process/symptom_ex_process.tex
index ffc1bb9..f27475d 100644
--- a/symptom_ex_process/symptom_ex_process.tex
+++ b/symptom_ex_process/symptom_ex_process.tex
@@ -194,9 +194,14 @@ output stage, and a failed internal audio amplifier,
 will both cause the same failure; $no\_sound$ !
 
 \paragraph{Collection of Symptoms}
-The common symptoms of failure are identified and collected.
+The common symptoms of failure and lone~component failure~modes are identified and collected.
 we can now consider the functional~group as a component and the common symptoms as its failure modes.
 
+Note  that here because this is bottom up, we can ensure that all failure modes
+associated with a functional~group have been handled. 
+It is possible here for an automated system to flag unhandled failure modes.
+\ref{requirement at the start}
+
 % \paragraph{symptom abstraction represented on the diagram} This process can be applied using a diagram.  From the collection of parts for the sub-system under analysis, a set of failure modes for each component is obtained. A diagram is then drawn with each component failure mode represented by a contour.  Component failure mode combinations are chosen for `test cases'.\footnote{Combinations of component failure modes can be represented by overlapping contours} A `test case' is represented on the diagram as a point or asterisk, in a region enclosed by the contours representing the failure modes it investigates.  The effect on the sub-system of each test case is analysed.  %It is then represented on the diagram by an asterisk on the contour representing the failure mode.  The `test~case~results' are archived.  When all test cases have been analysed, we switch our attention to a higher abstraction level.  % We treat the sub-system as a black box, or as a component part itsself.  % We can now look at the test case results from the perspective of a `user' % of this sub-system.  % % 
 % We treat the sub-system as a `black box' and view the effects of the component failure
 % at the sub-system level. This mean we are not interested so much in what the compoent does,