Forensics C

[personasaurus rex]

I'm almost finished with my flowchart for qualitative analysis. On average, how long should it take you to identify 8 powders? I'm going to time myself with this soon, but I'd like to know what a 'good' time would be beforehand.

Uh, could anyone answer this question? If it feels like I'm asking too many questions, I apologize, but State is in less than a week, and I'm desperately cramming.

I guess this differs from person to person and technique to technique. For 8 powders I can probably ID in around 10 minutes, but I guess I'm used to cramming and making a huge mess because the NY forensics proctor only allows you 40 mins for testing and I have to write the entire analysis and do polymers also...

[Dragonshark]

No such thing as too many questions – this one's just a little hard to answer. I know that, ideally, I'd like to spend between half and three-quarters of the full time (40 min, not counting cleanup) on powders, and the number of powders to identify can vary significantly. I guess 8 is a fairly low number of powders to have on an event... so I'd say probably 20 minutes.

It depends how you split the work between the partners. Usually my partner spends about 35 minutes doing powders while I do the polymers, chromatography, and physical evidence. Then we finish up any odds and ends, and write our analysis.

Yes, that's more or less how we split it up, as well – but a large fraction of the points (and typically most of the tiebreakers, when there are specific ones) are in the analysis, so it helps to have a significant chunk of time left to figure out what actually makes sense to write.

Around 20 minutes was what I predicted. My partner is going to work on polymers/chromatography, and after that, we'll both work on physical evidence and the essay. Hopefully that'll work out in the end.

Also, does anyone know how to tell the difference between human, other mammalian, bird, and amphibian/reptilian blood? I know human RBCs have no nuclei, but I'm not sure about the other ones. Finally, does anyone know how to distinguish dog and horse hair? From the pictures I've seen, they both appear to have very thick, solid medullas, but I don't know of any other distinguishing characteristics.

[Phenylethylamine]

I'm almost finished with my flowchart for qualitative analysis. On average, how long should it take you to identify 8 powders? I'm going to time myself with this soon, but I'd like to know what a 'good' time would be beforehand.

Uh, could anyone answer this question? If it feels like I'm asking too many questions, I apologize, but State is in less than a week, and I'm desperately cramming.

I guess this differs from person to person and technique to technique. For 8 powders I can probably ID in around 10 minutes, but I guess I'm used to cramming and making a huge mess because the NY forensics proctor only allows you 40 mins for testing and I have to write the entire analysis and do polymers also...

For me, it depends on what equipment is available at the lab station (and what you have to walk somewhere else to use), and what the powders actually are. I mean, if I have a sugar (and I'm trying to figure out which one), and the hot water bath is on the other side of the room, that's going to up my time significantly.

Plus I can't bring myself to make a huge mess... because the other thing the NY supervisor does is give you a relatively limited amount of cleanup time, and takes points off if you leave a mess.

[haverstall]

I'm almost finished with my flowchart for qualitative analysis. On average, how long should it take you to identify 8 powders? I'm going to time myself with this soon, but I'd like to know what a 'good' time would be beforehand.

Uh, could anyone answer this question? If it feels like I'm asking too many questions, I apologize, but State is in less than a week, and I'm desperately cramming.

I guess this differs from person to person and technique to technique. For 8 powders I can probably ID in around 10 minutes, but I guess I'm used to cramming and making a huge mess because the NY forensics proctor only allows you 40 mins for testing and I have to write the entire analysis and do polymers also...

While I don't test powders, I would say my partner gets 8 powders done in about 10-15 minutes. At Regionals and State, we've been able to at least double-check all the powders. In the same time, I did fingerprints, mass spectroscopy, and I think polymers? We didn't have to do a write-up though, so were weren't as cramped for time.

[Phenylethylamine]

While I don't test powders, I would say my partner gets 8 powders done in about 10-15 minutes. At Regionals and State, we've been able to at least double-check all the powders. In the same time, I did fingerprints, mass spectroscopy, and I think polymers? We didn't have to do a write-up though, so were weren't as cramped for time.

I should clarify: when I say 20 minutes for 8 powders, I mean to be sure (or as sure as I can get). That often includes multiple tests to double-check a particular powder, so that's built in to my time estimate. And wow, no write-up... lucky I've never had an event without significant analysis at the end.

[haverstall]

While I don't test powders, I would say my partner gets 8 powders done in about 10-15 minutes. At Regionals and State, we've been able to at least double-check all the powders. In the same time, I did fingerprints, mass spectroscopy, and I think polymers? We didn't have to do a write-up though, so were weren't as cramped for time.

I should clarify: when I say 20 minutes for 8 powders, I mean to be sure (or as sure as I can get). That often includes multiple tests to double-check a particular powder, so that's built in to my time estimate. And wow, no write-up... lucky I've never had an event without significant analysis at the end.

I was pretty sad about no write-up, but it does help keep your mind concentrated on just finding what is what. It also works in my favor, since I don't ever think I've actually succeeded in writing a quality write-up.
That being said, I do enjoy writing it; I'm just not that great at it.

[Steelfoam]

Does anyone have the order of beetles, not in my forensics book!

[Flavorflav]

Does anyone have the order of beetles, not in my forensics book!

Beetles are Coleoptera.

[Dragonshark]

Amazingly, we managed to win Forensics at state. The exam was pretty hectic and the supervisor wasn't exactly the nicest person in the world. We were worried that we would be disqualified because I formatted my notes such that I could rip out my flowchart for qualitative analysis while my partner had the notes for the other things, but that was apparently not allowed. Both of us didn't really know how to adjust the bunsen burners which were not like the ones we normally use, and the room smelled completely of gas, effectively masking the smells from burning fibers. There were things on the exam that I swear weren't on this year's rules, such as gas chromatography and arson. However, the chromatography was only matching pictures, which was much easier than developing a paper chromatogram. The question about arson asked why the victim's body didn't completely burn up from the fire. We didn't really know the answer to that question, so we just put down "oxygen deprivation." There was also an exhibit in the front of the room where we had 3 minutes to examine. It was an empty water bottle with some fingerprints on it, though it was pretty straightforward.

The supervisor also seemed to really want concise answers. We were allowed to write 5-10 words total for each section and were only given half a page to write the essay.

[bloods]

NY forensics test required knowledge of Sherlock Holmes. I feel so stupid for never reading that...