To clear a chart from a canvas in such a way that hover events cannot be triggered, we can follow these steps using JavaScript:

1. Get the reference to the canvas element.
2. Clear the canvas by resetting its width and height properties or by using clearRect() method.
3. Remove any event listeners attached to the canvas.

For example, we write:

// Get reference to the canvas element
var canvas = document.getElementById('myChartCanvas');

// Clear the canvas
canvas.width = canvas.width; // This resets the canvas width, effectively clearing it
// Alternatively, you can use clearRect method to clear specific area
// canvas.getContext('2d').clearRect(0, 0, canvas.width, canvas.height);

// Remove event listeners (assuming you have attached events to it)
canvas.removeEventListener('mousemove', mouseMoveHandler);
canvas.removeEventListener('click', clickHandler);

Replace 'myChartCanvas' with the actual id of your canvas element.

This code will clear the canvas and remove any mouse-related event listeners (like hover events) attached to it.