Resources

Our products are for a technical scientific industry, and there are often multiple product variations or custom options for different applications. We prefer to make sure that our customers are purchasing exactly what they need before receiving an order, especially for the more expensive items or larger orders. We will be making more standard items like filter cassettes available for e-commerce purchases in the near future.

Yes, we design and manufacture almost everything we offer. We use a network of trusted local vendors for specialty manufacturing processes such as laser cutting, anodizing, and sheet metal forming, etc. For the most stable and consistent supply chain, we avoid offshore manufacturing and use as many USA-made components as possible, except for a few minor items such as electronic components and filter materials. For specialty items like motors, we carefully select vendors with a reputation for quality.

Yes. Supplying items to other instrument manufacturers and companies is a big part of our business. An OEM Original Equipment Manufacturer arrangement often includes supplying our standard products, or supplying custom-designed exclusive and non-exclusive products. We also contract manufacture items based on customer designs, especially proprietary air sampling inlets.

Yes, we sell directly in over 30 countries. We also have a number of authorized resellers and distributors located around the world. Our reseller discounts are currently based on annual and individual order quantities. We have not currently offered any exclusive international distributorship regions. However, we do offer a few exclusive individual products in certain regions, and we are considering offering exclusive distributorships for our new complete air sampler instruments in the near future. Please inform us if you are a new reseller and provide any exempt tax ID number when placing an order. The international buyer is responsible for paying for all import taxes, tariffs, duties, and fees.

Our PayPal merchant account is set up to securely process international credit cards online. You are not required to have a PayPal account to pay with a credit card through this system. This is the best payment option for international credit card holders placing orders totaling up to approximately $2,000. We may require wire transfer payments for larger orders due to processing fees. US and Canadian customers may pay us directly with a major credit card.

PM_2.5 and other air monitoring cyclones are not designed to directly trap water or large debris, which can clog or corrode the inside passages. Also, high concentrations of pollen or other particles larger than the rated cut-point can overload the cyclone. For this reason, a PM₁₀ inlet is always required as a pre-separator for outdoor regulatory applications. For very low flow rate applications such as our 2.0 L/min mini cyclone series, a simple TSP inlet is usually sufficient to block water and debris above a cyclone, but frequent inlet cleaning may be required.

In general, the inside of the particle trap area in all PM₁₀ and PM_2.5 impactor or cyclone inlets must be cleaned at least every 30 days (monthly) according to most government regulations and guidance documents. WINS Impactor oiled substrates must be cleaned and replaced weekly. The rest of the inside surfaces of particulate inlets should be opened and cleaned at least every 90 days (quarterly). Local SOPs may require more frequent cleaning intervals, especially in high PM concentration locations.

Air sampling cyclones and impactors use the inertia of individual particles moving at a fixed flow rate velocity to separate and trap those larger than the rated “cut-point” size, while allowing the smaller particles through the inlet. This of course requires an assumption about the mass density of the particles. A perfect PM_2.5 inlet would trap 100% of all particles larger than 2.5 microns, and 0% of the smaller particles. A graph of the penetration efficiency vs particle size for such an ideal inlet would show a vertical drop-off from 100% to 0% at exactly 2.5 microns. However, this separation efficiency is never 100%, but is instead a logarithmic decay curve, where the 50% efficiency point, or “D50” point, is centered at the rated cut-point size. The “sharpness” of the cut-point is simply how steep this curve is, the sharper the better. As a practical matter, this means that if the actual air sample contains particles very close to the rated cut-point size, then a small percentage that should be trapped will get through, and vice versa. Though imperfect, this method is at least consistently defined for regulatory purposes.

Air sampling cyclones and impactors use inertia to separate particles, so the rated PM cut-point size is only accurate at the exact design airflow rate, and accurate airflow control is required. Cyclones and impactors can sometimes be operated at a different flow rate in order to obtain a different cut-point within a reasonable range. For example, our AE10-2 cyclone is for PM₁₀ at 2.0 L/min, but can also be used for PM_2.5 at 6.7 L/min. We can calculate the theoretical cut point for any reasonable flow rate for any of our standard inlets, and we can also design custom inlets for any practical cut-point and flow rate.

TSP is Total Suspended Particulate, and was also sometimes referred to as SPM Suspended Particulate Matter in older documents. TSP is a general term for all particulate that stays suspended in the air more than just momentarily, and is sometimes defined as all particles up to 100 microns. TSP particulate total mass tends to be dominated by plant pollens, which are almost always larger than 10 microns, or inconsistent low density particles like fine sawdust. Unlike smaller PM₁₀ where the individual particle compositions and densities are usually fairly consistent, TSP particle mass density can vary widely, often resulting in a poor correlation between particle mass and aerodynamic diameter. For these reasons, TSP is not regulated like PM_2.5 and PM₁₀. A perfect TSP inlet would be a funnel pointed straight upward, but as a practical matter TSP inlet designs are always a compromise between excluding rain water, insects, and large debris, while allowing passage of most particulate into the inlet.