How must thermoplastic powders be applied to a surface?

The correct method for applying thermoplastic powders to a surface is through the use of an atomizer. Atomizers are specialized devices that disperse a liquid in a fine spray, ensuring an even and controlled application of the powder. This method is particularly effective for achieving a uniform coating and reducing the potential for clumping or uneven distribution, which can occur with other application techniques.

Using an atomizer allows for better control over the amount of powder being applied and can enhance the visibility of prints by maximizing the surface area coverage. This is critical in latent print examination, where precision in applying powders can significantly impact the development of latent fingerprints.

In contrast, while brushes, sprays, and dip methods can be used in various powdering techniques, they may not provide the same level of consistency and control as an atomizer. For instance, brushing may lead to uneven coverage, and dipping can result in an overly thick application, both of which could obscure the prints instead of revealing them effectively.