Year 2007 has arrived amid soggy wet warm weather in the East and heavy snow fall in the Mid-west. We are also mourning the death of a president and more soldiers killed in Iraq. Amid all this we still move on with expectations and resolutions for this New Year. I for one, hope to bring you up to date on changes in protective clothing standards, testing and equipment as I have done in the past.
As I reported in my last column, ASTM Committee F23 is now designated F23 On Personal Protective Clothing and Equipment. Currently there are 44 standards under the jurisdiction of this committee addressing chemical, physical, biological, radiological, thermal and flame resistance of protective clothing. All of these standards come under review almost every three years. Of particular interest this year, are changes and revisions to F739.99a the first chemical permeation test method developed by committee F23 in 1983. The original title of this method was Standard Test Method for Permeation Testing of Protective Clothing For Resistance to Liquids and Gaseous Chemicals. The suggested new title is now Standard Test Method for Permeation of Liquids and Gases through Protective Clothing Materials Under Conditions of Continuous Contact. Although this change seems minor, it does clarify that testing is done continuously rather than for intermittent contact as in spills or splashes. Other major changes to the method include the requirement to do tests at 27ºC instead of ambient temperature and that the recommended test cell is now the one inch glass permeation test cell. The requirement to do testing at 27ºC using the one inch cell will necessitate using either submersible cells in a water bath or maintaining the standard one inch cell in a temperature controlled atmosphere or chamber. Using the one inch cell does make sense, since most of the permeation tests that are done report using this cell because it requires less chemical and sample size for testing and less waste generation. The other significant revision to the method is the addition of the recent inter-laboratory test results for precision. These results should help new laboratories just starting up to do permeation testing to compare their data on reference materials such as the standard 16 mil neoprene used in the original round robin tests. Remember this reference neoprene is available from Pesce Lab Sales. The order number for the neoprene and part numbers for the one inch test cell can be found on the Pesce Lab Sales web page, www.pescelabsales.com. These proposed changes and revisions are being voted on now by members of the F23.30 committee on Chemicals and will be reviewed at the F23 committee meeting in Anaheim, California January 31–February 2, 2007. If the results are all affirmative with no negatives the changes will become official at the end of the meeting. Also of interest to users of this method is a computer program being developed by NIOSH that takes data from permeation test results and calculates breakthrough time and permeation rates automatically based on the standard test cell and analytical sensitivity. This could eventually become part of the test method too and would reduce potential errors in reporting permeation data. So we will stay tuned to the outcome of the meeting in Anaheim.
Norm Henry