Start by inspecting the film's physical condition for visible signs of wear. Look for cracks, tears, or holes—even small gaps can let moisture, dust, or pests enter the bale, compromising the cotton inside. If the film appears brittle or has become discolored, it may no longer provide a reliable barrier. Additionally, check for areas where the film has peeled away from the bale or lost its tension; loose film fails to hold the bale securely and leaves parts of the cotton exposed.

Assess the film's ability to maintain its protective properties. If you notice moisture spots on the cotton or signs of mold growth when inspecting the bale, this indicates the film's moisture barrier has weakened or failed. Similarly, if dust accumulates inside the wrapped bale, the film is no longer preventing external contaminants from entering. For outdoor-stored bales, pay extra attention to film degradation from sunlight—UV exposure can make the film fragile, even if surface damage isn't immediately obvious.

Consider the duration of use and storage conditions. Even if the film looks intact, prolonged exposure to harsh environments such as extreme temperatures, high humidity, or frequent temperature fluctuations can break down its material over time. Bales stored in these conditions may require more frequent film checks and earlier replacement. Also, if the bale is moved or handled multiple times, the film may develop hidden damage from friction or impact.

Evaluate the film's functionality during handling. If the film slips or tears when moving the bale, or if it no longer holds the bale's shape, it can't provide the necessary support or protection. Replacing the film at this stage prevents the bale from unraveling and keeps the cotton safe until it's ready for use. By combining visual inspections, checks for protective failures, and consideration of usage conditions, you can determine the right time to replace used cotton baling film.