Which of the following can impair the function of a harness?

The presence of paint on the webbing of a harness can impair its function significantly. Paint can obscure the webbing's fibers, potentially hiding signs of wear, damage, or degradation that could compromise the integrity and safety of the harness. Additionally, paint may contain chemicals that can react with the materials of the harness, weakening them over time. It is crucial for harnesses to remain free of substances that can obscure inspection or degrade material strength, ensuring they remain reliable during use.

Other factors like obstacle attachment points can be necessary for certain operations and do not impair the harness itself directly. Excess cleaning solutions, while they can lead to other issues, typically do not affect the harness's fundamental structure. Lastly, old manufacturer guarantees relate to safety standards and confidence in the harness rather than its physical condition. Ensuring that webbing is clean, intact, and free of obstructions is essential for maintaining harness efficacy and safety.