(952) 894-8737(800) 718-8737


Please refer to the following list of commonly asked questions and answers before contacting us for help. If your question is not answered here, please get a hold of one of our representitives through the contact page.

What is the bulk density of the ISO 12103-1 Test Dust grades?

  • ISO 12103-1, A1 Ultrafine Test Dust – 500 kg/m3
  • ISO 12103-1, A2 Fine Test Dust – 900 kg/m3
  • ISO 12103-1, A3 Medium Test Dust – 1025 kg/m3
  • ISO 12103-1, A4 Coarse Test Dust – 1200 kg/m3

What is the Specific Gravity of the test dust contaminants we sell?

The specific gravity is 2.65.

What is the particle count of the ISO grades of test dust?

We provide particle size analysis using various techniques but we do not perform particle counting. Please click on the following link for information regarding particle-counting services: Interbasic Resources, Inc www.ibr-usa.com.

We receive many questions regarding ISO, SAE and AC Test Dusts. For answers to most of these questions please read the “Test Dust History”

We are concerned about contamination from the equipment as well as from previously processed materials, what procedures are in place to prevent contamination?

  • Each machine is dismantled, blown out with compressed air, vacuumed and washed thoroughly with soap and water. Work instructions detailing our cleaning procedure are in place for each piece of equipment; they are reviewed on a regular basis.
  • All wear areas of our equipment are lined to prevent contamination or discoloration.

What materials have you processed?

  • Please go to our Materials Processed page for a list of materials processed.
  • We will not process hazardous materials or materials which are potentially explosive or flammable.

What particle sizes are attainable with your current equipment?

  • Jet milling: Particle sizes attained from jet milling are as low as a 4-micron median to as high as a 45-micron median. Jet milling is best suited for distributions ranging from 0-150 microns.
  • Hammer milling: Best suited for coarser distributions ranging from as low as ~20 microns up to ~ 2000 microns.
  • Vibratory screening: Screen sizes from 38 – 4800 microns are available.
  • Air classification: Particle size distributions as tight as nominal 0-3 microns and as broad as nominal 0-45 microns can be achieved.
  • Jaw crushing: Primarily used as a pre-crushing step for material that is too large to feed into a secondary mill, such as a jet mill or hammer mill. Our jaw crusher can reduce material as large as 5” x 7” down to minus 10 mesh in one pass.

What is your processing capacity?

We can process as little as 25 pounds up to approximately 3 million pounds per year per process.

What yield can I expect?

Yield Expectation:

  • Jet milling: Typical yields are 95-98%
  • Air classification and Vibratory Screening: Yields will vary depending on raw material particle size distribution and the desired final product size distribution.
  • Hammer milling: Yields will vary depending upon the friability of the raw material and the desired final product size distribution.

How much will it cost to process my materials?

  • To provide processing cost quotations on your materials, tests are required. Tests and small lot processing jobs are performed on a fee basis for non-toxic and non-hazardous materials. The fee includes setup, processing, cleanup, and any required particle size analysis. Most test programs are 1.0 to 2.0 days duration. A one-time fee is assessed for collector filters; which are retained for your future processing requirements. Please call or email for test costs.
  • When testing is complete we will provide you with a detailed cost quotation for the quantities you indicate.

How much material will you need to run a test?

In order to determine optimal machine settings we will need a minimum of 100 pounds of feedstock. We can work with less material, however the chances are we will not be able to determine maximum throughput, which will hinder us from giving you our best price for production runs.

What do you need prior to starting a test run?

  • A current Material Safety Data Sheet (MSDS)
  • If available, a 5-10 gram control sample representative of the desired particle size.
  • Detailed list of requirements, including the following:
    • Approximate raw material particle size.
    • Desired particle size(s).
    • Method of analysis. (Please view our list of available particle size analysis techniques under the “Size Analysis Services” page.)
    • Packaging requirements.
  • If you are a new customer to PTI, we will need your companies trade references and a purchase order with detailed company information, please include your preferred shipping carrier with account number, if applicable. We also accept Visa and Mastercard.

What packaging options are available?

We can package into containers from 1 gallon up to 4,000-pound super sacks. We can package into Kraft bags in a limited quantity.

What is the advantage of using a jet mill process over another type of milling process?

The type of jet mill we use generates a distribution that is “stacked” towards the coarse end and does not create a large amount of, sometimes, unwanted fine material. If the fine particles generated are a concern we can use a secondary air classification step to remove those particles.