What is one of the main uses of portable heaters in fingerprint development?

Portable heaters play a crucial role in the process of fingerprint development by accelerating superglue fuming. Superglue fuming, or cyanoacrylate fuming, is a technique used to develop latent fingerprints on non-porous surfaces. This method involves the application of heat, which increases the rate at which the superglue vaporizes. When heated, superglue vapors adhere to the moisture and oils present in the latent fingerprints, forming a white visible print.

The use of portable heaters in this context allows for faster and more efficient development of fingerprints, as the increased temperature enables the fuming process to occur more thoroughly and quickly. This is particularly beneficial in forensic investigations where time is often of the essence, and the ability to quickly reveal fingerprints can be critical to the success of the investigation.

While the other alternatives mention drying evidence or increasing powder adhesion, they do not directly relate to the primary function and effectiveness of superglue fuming in fingerprint development, which is why accelerating this process with heat is the main focus when using portable heaters in this context.