cracked concrete becomes safety hazard for employees and customers

At What Point are Damaged Concrete Surfaces a Safety Issue?

The daffodils might not be the only things coming up from the ground as signs of spring begin to appear. In colder-weather climates, new cracks and other concrete surface damage are also showing their faces.
But at what point is this damage more than an aesthetics issue? When is it cause for concern for employee or customer safety? And how should it be addressed?