Warnings - clarified with Mark K

Author: Irit Arkin

docs/reference/api/rtos/Mutex.md

@@ -4,7 +4,7 @@
 
 A Mutex is used to synchronize the execution of threads, for example to protect the access to a shared resource.
 
-<span class="warnings"> **Warning - ISR:** The `Mutex` methods cannot be called from interrupt service routines (ISR). In the current version of Mbed OS, if you attempt to use a mutex from within an ISR, nothing happens; attempts to lock a mutex succeed immediately, regardless of whether the lock is actually free. In other words, if you acquire a mutex lock in an ISR, you can break the thread safety mechanisms and introduce race-conditions into an otherwise safe piece of code. Future versions of Mbed OS will provide warnings and ultimately prevent this from happening. </span>
+<span class="notes"> **Note:** The `Mutex` methods cannot be called from interrupt service routines (ISR). In the current version of Mbed OS, if you attempt to use a mutex from within an ISR, nothing happens; attempts to lock a mutex succeed immediately, regardless of whether the lock is actually free. In other words, if you acquire a mutex lock in an ISR, you can break the thread safety mechanisms and introduce race-conditions into an otherwise safe piece of code. Future versions of Mbed OS will provide warnings and ultimately prevent this from happening. </span>
 
 <span class="images">![](https://s3-us-west-2.amazonaws.com/mbed-os-docs-images/Mutex.png)</span>
 

docs/reference/api/thread_safety.md

@@ -74,7 +74,7 @@ The RTOS provides several mechanisms to move interrupt processing onto a thread.
  - [Queue](https://os-doc-builder.test.mbed.com/docs/development/mbed-os-api-doxy/Queue_8h_source.html).
  - [Mail](https://os-doc-builder.test.mbed.com/docs/development/mbed-os-api-doxy/Mail_8h_source.html).
 
-<span class="warnings">**Warning:** In Mbed OS 5, if you attempt to use a mutex from within an interrupt, nothing happens; attempts to lock a mutex will succeed immediately, regardless of whether the lock is actually free. In other words, if you acquire a mutex lock in an interrupt, you can break the thread safety mechanisms and introduce race conditions into an otherwise safe piece of code. Future versions of Mbed OS will provide warnings and ultimately prevent this from happening.</span>
+<span class="notes">**Note:** In Mbed OS 5, if you attempt to use a mutex from within an interrupt, nothing happens; attempts to lock a mutex will succeed immediately, regardless of whether the lock is actually free. In other words, if you acquire a mutex lock in an interrupt, you can break the thread safety mechanisms and introduce race conditions into an otherwise safe piece of code. Future versions of Mbed OS will provide warnings and ultimately prevent this from happening.</span>
 
 For more information see [rtos/Mutex.h](https://os-doc-builder.test.mbed.com/docs/development/mbed-os-api-doxy/Mutex_8h_source.html).
 
@@ -88,7 +88,7 @@ For more information see[platform/critical.h](https://github.com/ARMmbed/mbed-os
 
 Critical sections disable interrupts to provide uninterrupted access to a resource, so you can use critical sections to make code **interrupt safe**.  However, you should avoid using critical sections if you can, because they must execute quickly, or they will cause system instability.
 
-**Warnings**:
+**Notes**:
 
 - Do not perform time consuming operations inside critical sections. This will negatively affect the timing of the entire system, because all interrupts are disabled during critical sections.
 - Do not invoke any standard lib or RTOS functions within a critical section; it could result in a hard fault because RTOS performs SVC calls.