GRAP 2 is not explicitly mentioned in the provided evidence, which discusses GRAP-3 curbs. However, based on the context, it can be inferred that GRAP 2 is a previous or related measure. The evidence does not provide detailed information on how GRAP 2 works.
GRAP-3 curbs, as mentioned in the evidence, include a work-from-home policy, a ban on vehicles, and a halt on construction. These measures are likely part of a broader strategy to control the spread of COVID-19 or a similar public health crisis. The exact mechanisms and goals of GRAP 2, if it exists, are not specified in the provided evidence.
The evidence does not provide a clear explanation of how GRAP 2 works, as it focuses on the specifics of GRAP-3. It is possible that GRAP 2 is a precursor or a component of GRAP-3, but without further information, it is difficult to provide a detailed answer.