MSTC
Certificate of Findings
Methylene Blue Test for Residual Thiosulfate
Date Tested: 7/21/2004
é
Client Contact
Client
Street Address
ë City, State, Zip
Country
Film
Description: Sample
MSTC has
tested your film sample for residual thiosulfate ion concentration. Testing was done in accordance with the methylene blue
method described in ISO Standard 18917:1999, Photography-Determination
of Residual Thiosulfate and Other Related Chemicals in Processed
Photographic Materials-Methods
Using Iodine-Amylose, Methlyene Blue and Silver Sulfide.
Film containing thiosulfate concentrations of 0.014 grams per
square meter, or less, meets the requirements of ISO 18901:2002, Imaging
Materials -
Processed Silver-Gelatin
Type
Black-and-White Films -
Specifications
for Stability-500
year microfilm (previously referred to as “archival” film).
This is the same requirement listed in the Federal Code of Regulations
36CFR-1230.14(c)
Processing Standards,
for permanent records, as published under the direction of the US Government’s National
Archives and Records Administration.
Please note that long-term film
stability depends on the physical and chemical nature of the film, its
residual thiosulfate level in the case of wet processed silver-gelatin
films, and the conditions under which the film is stored.
|
Test Number
|
Date Processed
|
Film
Size
|
Actual
Concentration
In g/m2
|
Meets
ISO
Standard for
LE-500 Film
|
|
3405
|
7/18/2004
|
35 mm
|
0.001
|
Yes
|
Certified by:
________________________________
Michael
L. Thomas
Photographic Scientist
The methylene blue test is only
meaningful and accurate if performed within two weeks after film
processing. It is MSTC’s
understanding that we have received your film within the two-week time
frame.
ã MSTC
2004
Management
Systems Technology Consultants, LLC
5585 Old Farm Lane / Manassas,
VA 20109-2118 /
Fax: 703
754-9963 /Tel:
703 754-3213
