The shards of glass are hazardous to humans and can have an effect like bleeding out if a main vain is hit.
Using new glassware for each investigation.
If it is laboratory glassware, you want to avoid contamination. Bacteria or chemicals left on the glassware could react and give an inaccurate result.
To get rid of germs.
wash hands and clean glassware
The FBI started their investigation.
Wear safety glasses when cutting glassware no matter where you are.
To the right directly above the knife.
The police launched an investigation into the theft of the valuable artwork.
What method should be used to clean glassware in a labortory
by using a hot water and chromic acid
investigation
Using a balance to measure mass might be part of a scientific investigation, but by itself and under ordinary circumstances it does not amount to a scientific investigation. If you are on a different planet or on a moon, or if you were in the weightlessness of space, then doing this (or trying to do it) might be considered a kind of investigation.