diff --git a/Pasted image 20210719010634.png b/Pasted image 20210719010634.png
new file mode 100644
index 000000000..91bfe9970
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diff --git a/stpa handbook.md b/stpa handbook.md
index 1682ff104..cc9669548 100644
--- a/stpa handbook.md	
+++ b/stpa handbook.md	
@@ -58,4 +58,8 @@ On [[control]] proper:
 
 tips to prevent common mistakes in a control structure: 
 
-![[Pasted image 20210719010243.png]]
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+![[Pasted image 20210719010243.png]]
+
+Step three:
+
+![[Pasted image 20210719010634.png]]
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diff --git a/system theoretic process analysis.md b/system theoretic process analysis.md
index 0badcff72..537679f06 100644
--- a/system theoretic process analysis.md	
+++ b/system theoretic process analysis.md	
@@ -28,5 +28,6 @@
 		- [[responsibilities]] can be assigned to each control structure entity; they are refinements of [[system level constraints]]
 		- [[feedback]] can be derived from [[responsibilities]] (which information does the process model need to contain?)
 	- step three: [[identify unsafe control actions]]
-		- an [[unsafe control action]] is 
+		- an [[unsafe control action]] is one that, in a particular context, will lead to a [[hazard]].
+		
 	
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