How should glass evidence be collected according to the guidelines?

When collecting glass evidence, it is crucial to handle the larger edges only to minimize the risk of contamination and preserve the integrity of the evidence. The larger edges provide a safer way to handle the glass without compromising its potential to retain trace evidence or fingerprints. This technique ensures that the evidence can later be analyzed accurately in relation to the case.

Addressing the other choices, crushing glass into smaller pieces would destroy its structural integrity and remove valuable evidentiary information. Collecting glass from flat surfaces is important, but it is not specifically about how to handle the pieces of glass itself, making it less relevant as a method of collection. Using surgical tools may help in some cases, but it is not a standard guideline for glass evidence collection and could introduce other risk factors if not done correctly. Thus, emphasizing the handling of larger edges is the most effective and appropriate technique for preserving glass evidence.