The test method you should use depends entirely on the scope of the analysis. If the analysis is for a regulatory purpose you should consult with that specific agency to determine what method they require. If this is for research type purposes there are a few different methods that can be used. The EPA suggests using methods out of SW-846 for digestion of solid samples, such as Method 3050B or Method 3051A. There is also an ASTM method designed specifically for this purpose - E1644 Practice for Hot Plate Digestion of Dust Wipe Samples for the Determination of Lead.

The GhostWipe is designed to be used for dust sampling on surfaces for lead and beryllium. We do not test the wipe for the presence of any other contaminants. Some users have reported success in using the wipe for other metals. To do so, you would need to check each lot of wipes for background levels of your analytes of interest. Take as many wipes as you need for a good statistical evaluation (a minimum of 5-7 is recommended) and analyze them individually as blanks. Average the results of the contaminants that you have an interest in and use that as a background correction for future analyses with that lot. I do not know if cyanide will be adequately captured using the wipe procedure. The tank wall conditions will also affect the stability of the wipes. Depending on the amount and strength of acidic residue left on the inside of the tank you may experience some degradation of the wipe.

When using products for compliance with regulated methods all expiration dates must be observed to ensure valid results. The GhostWipe is moistened with reagent water to aid in picking up dust particles from the surface(s) of interest. The expiration date given is the length of time we know that the packaging will retain the required amount of moisture and the wipe will retain its needed durability to withstand the wiping process.

Yes, the GhostWipes are the same material for both the regular and the beryllium version. The only difference in them is the size of the wipe. I believe the size is specified for each wipe testing procedure.

The GhostWipes have an expiration date of 2.5 years (30 months) from the date of manufacture.

The GhostWipe is intended for use in lead and beryllium testing. As such, these are the only two metals for which we do background testing and issue certifications of cleanliness. If you wish to test for other materials it would be your responsibility on a per lot basis to test and decide if the GhostWipe would provide an appropriate level of detection for you. We have had other customers report successful use of the GhostWipe for other metals, including chromium. If your local authorities state that they are not appropriate for what you want, there is not much we can do to counter that. The wipes are made of polyvinyl alcohol and do not contain MCE.

While the mechanism of the Ghost Wipe is suitable for sampling many different surface contaminants, the Ghost Wipes were developed specifically for the sampling of lead and beryllium. We only certify the background levels of these two metals for each lot. To determine the suitability of the Ghost Wipe for an analyte other than the two certified you would need to conduct your own testing per lot for background levels.

We used a method following HUD (Housing and Urban Development) guidelines for Lead in Dust Wipes Appendix A-5.0 which references NIOSH 7082. 10 mL of DI water is added to the container with the wipe. Then 2 mL each of hydrochloric and nitric acid are added. The sample is digested at 95 C for 45 minutes. After digestion and cooling, the sample is brought up to 50 mL with DI water. It is now ready for analysis.

We do not certify the Ghost Wipes for any metals other than Lead and Beryllium. In order to determine the appropriateness for any other metal, you would need to do your own validation study. If you would like we can send you a sample pack of the Ghost Wipes that you can test for mercury levels as blanks. This will give you an idea of if the background amounts are below your needed detection limits. You would need to do a similar study for each new lot of wipes that you receive. If you would like the sample pack, please call in to any of our technical help lines or sales lines for assistance.

The Ghost Wipes are pre-moistened with deionized water which is certainly safe for contact on human skin. There are no other chemicals in the solution.

Please contact sales@envexp.com for all pricing inquiries.

Our 50mL digestion vessels, cat# SC475, can be ordered without the caps. The catalog number is SC474 and pricing is based on volume as follows: 1-2 $100, 3-5 $97, 6-9 $92, 10+ $87.

The wipes are wetted with DI water and each wipe is contained in a foil pack

This is something we could do for you. Please contact me at 800-343-5319 or joeb@envexp.com.\r\nJoe Boyd