CLPEX Chat Board

Hi,

I'm looking for some / any information on the effect of humidity on the persistence of latent marks and whether anyone could point me in the direction of some pertinent studies. I am aware of this paper "The Effects of Temperature and Humidity on the Permanency of Latent Fingerprints
P.D. Barnett, R.A. Berger c. 1975" however the results seem somewhat inconclusive. From what I can determine the humidity and the requisite heat could affect the aqueous constituents of the mark and indeed the salts in a reasonably short amount of time (within 24hrs) but would not necessarily prevent the mark being developed. I understand there are countless variables and enviromental factors that influence latent mark recovery and no two cases are the same, however any info or suggestions of substantive studies would be of great help!!

"Results of Time, Temperature and Humidity on Latent Fingerprints": Bluhm, Richard J. and Walter J. Lougheed; Identification News, Jul (1968)

I don't have a copy of this article, just the reference. Most other articles I've seen are related to processing, with or without humidity, using different techniques.

Hi Steve,

Thanks for the info, i'll try and locate a copy

I have attempted to attach a .pdf copy of the article, but not sure if it got downloaded.

Hi Ernie,

Thanks very much for the download - works fine - much appreciated.

I hate to complain, but it seems the article isn't complete . . . missing pages.

Hi Kossman, I think its the page order spread across two issues, the order appears to be pg 14 July 68, pg 15 July 68, pg 5 Aug 68, pg 10 Aug 68, pg 11 Aug 68. There may be subsequent pages in the Sept 68 issue as it says "cont next month" on the bottom pg 11

Sorry about that!! I no longer have the original that was used in generating the .pdf, but I am sure it recorded all that I had at the time, which was only a copy of the article (not an original issue) as 1968 was a few years before I started receiving Identification News. I believe the IAI did a CD with all issues of ID News, so someone should have the complete article.