With the firmware update to Android Lollipop on your Samsung Galaxy S5 much has changed. Not only system processes and apps have been optimized, but also the graphical interface has received a lot of new details and changes. This includes the design of the lock screen.
On the lock screen you will have noticed with certainty that in the lower left corner a small icon is visible as a red handset. Moving the icon in the center of the screen, the emergency mode appears in which, for example, the emergency call or own emergency contacts can be called without unlocking the Samsung Galaxy S5.
Now you may ask yourself:
Can I remove or hide the red handset on my Samsung Galaxy S5 lock screen?
The answer is: No.
The fact is that smartphone manufacturers are obliged to give the possibility to make an emergency call with a locked phone. This Feature Samsung has implemented on the Samsung Galaxy S5 in Android lollipop with the red handset icon on the lock screen.
Maybe this will change in a future firmware update again, but one can assume that Samsung contents itself with the red handset icon.