Double-state switch control challenge for nonexperienced users

Question

I have a challenge to optimize one service for sensor panel. It has a table with equipment list, and the user can manually change the state of every equipment — to "normal" or "failure" (only two choices):

Other contexts of the task: the users are not experienced in computer interfaces, using fingers to change the state, and they should notice only failure states (visually accented), not normal. In current realization of interface user clicks the button and selects from these two states in pop-down list (two finger clicks on the surface of sensor screen).

So this is my challenge -- is there any way to make this control require one click (as checkbox), but that they will understand, that this button will change to another state (not lead to another page, or to dropdown menu).

"On/off switch" would be the ideal control, but this is not on/off switch, it is "normal/failure" switch, and due to long labels it is too large in the table (the original labels are on russian and are even longer, than english ones).

Checkbox is also not an alternative, because it doesn't show the exact name of the second state (but it seems that I will use it if there is no another, better way).

Update: Do you think it is a good solutions (the current state is clear, and the possibility to change it to some another by clicking or draging is also clear):

Answer 1

You could use a physical looking toggle switch with a red light.

E.g. these three commercial search results

1. http://depositphotos.com/1194534/stock-illustration-Toggle-Switch.html
   

2. 
   

3. 
   

Answer 2

Your second screen shot is very similar to the toggle switches I have on my LG touch screen phone and (from what I recall) the "usual" iPod/iPad toggle buttons, which seem (to me) to convey the state information you wish to impart.

I'd go with that design.

Even the most inexperienced users soon pick up on what's required to manipulate controls.

Answer 3

Like ChrisF, I'd first suggest emulating the iPhone / iOS toggle buttons:

These switches take a strong colour when 'active' (you could use a red for the 'warning' state), and belie the state in the switch appearance. Be sure the 'background' space looks recessed, typically by using a slightly darker colour than the switch element itself. Your current design's background is probably too dark, and the red warning element doesn't look raised against it.

The other convention that comes to mind is 'flagging', with warning icons that can be toggled on or off with a touch. The icon itself could be a flag, or perhaps something like an exclamation mark:

You'd probably want to tweak the above to give the exclamation links more affordance, but you get the idea.