Please click on the following information to learn more about how the Vapor Pin® can assist in your field testing
We can’t rule out leakage, but it’s rare with Vapor Pins®, and if you detect helium at multiple sample points, it might be caused by false positives from methane. Most helium detectors respond positively to methane. Similarly, high concentrations of C5-C12 hydrocarbons in soil gas have been reported to cause false positives in helium detectors. Methane generation is common when oxygen is depleted by high concentrations or large sources of hydrocarbons, especially in petroleum products containing ethanol. This is one of the reasons that Cox-Colvin encourages leak testing via mechanical means, as described in our SOP Leak Testing the Vapor Pin® via Mechanical Means (located under our Resources Page), and as discussed in the Interstate Technology & Regulatory Council (ITRC), 2014 Petroleum Vapor Intrusion guidance. If you do use a helium leak detector, we recommend using a model that does not respond to methane, and test the soil gas for false positives before applying helium.
At checkout, shipping choices will be listed in a dropdown list after you enter your address and zipcode.
Fedex Express picks up 4:00 PM Ground picks up 9:00 am EST.
You could also go Fedex.com to determine transit times. Put in our zipcode for where its coming from (43064) and enter your shipping zipcode destination.
We currently have Distributors in Australia, Brazil, Canada and Europe.
For Australia orders –
For Brazil orders
USA | Central America | South America
For Canada orders
Contact Hoskin Scientific
Burlington, Ontario – Serving Ontario and Maritime provinces
4210 Morris Drive,
Burlington, ON L7L 5L6
Toll Free (800) 665-5871
Email salesb@Hoskin.ca – www.hoskin.ca
For Europe orders
Contact Mark Byrne – Ribble Group
Ribble Enviro – Unit 4 Gisburn Business Park,
Gisburn, Clitheroe, BB7 4JP, UK
Toll Free 01200 445 804
Email M.Byrne@ribble-enviro.co.uk – www.ribble-enviro-co.uk/a>
Use 16mm for the pin and 38mm for the covers, we suggest 400mm cutting length for both sizes.
The FLX-VP was specifically designed to connect to a variety of other devices including Swagelok compression fittings. The standard Swagelok connection for 1/4” OD Nylaflow and Teflon tubing, and for TO-17 sorbent tubes is available through the Vapor Pin® website (Part Number SL_FLX1_Fitting). Replacement ferrule sets are also available.
First and foremost, there may be specifics required by regulators in your state…by in general…
Silicone tubing is more reactive than harder tubing, which is to say that Silicone, and softer tubing generally, is more prone to absorbing and outgassing organic compounds. Greg Ouellette’s 2004 Soil Vapor Sampling and Analysis – Lessons Learned, DOE/PERF Soil Vapor Workshop, Brea, CA Jan. 27-29, is one of several reports that demonstrates the higher reactivity of soft tubing, this is out of context for our application. Ouellette drew vapors through 50 ft of Tygon tubing, which has approximately 85 square inches in contact with soil gas. In the case of the Vapor Pin®, the only contact between soft tubing (Silicone) and soil gas is the cross sectional area between the slab and the bottom of the pin, which is 0.11 square inches. I think we also agree that while Silicone would absorb some VOCs, the tubing would reach equilibrium at some point and stop absorbing vapors.
We test the Silicone tubing when it arrives by drawing ambient air through the entire 50 ft lengths with a PID, and record the readings. The tubing does contain a few ppm of vapors in the first few days, specifically siloxanes, which are not on any vapor intrusion list. We continue to test for several days until the entire length of tubing contributes less than 1 ppm of VOCs. We then cut the tubing into short lengths and let them continue to air before sending them.
They are relatively obscure issues such as what kind of helium to use during leak testing, or whether to use barbed versus compression fittings, when most of the problems boil down to a few issues:
1) Run a shut-in leak test on the assembled canister & regulator, as described in ASTM D7663-11, before going to the field. Leak test the assembled sample train on site, except for the connection to the Vapor Pin® or equivalent point with a hand-held vacuum pump or peristaltic. Last, connect the sample train to the sub-slab point and leak test it the point. Helium works, but we use distilled water. That’s a problem if the point leaks, but I’ve never seen it with the Vapor Pin®. We also check the regulator flow rate prior the shut-in test, but an improper flow rate is more likely to result in no sample than an invalid sample. We’ve developed our own techniques if you’re interested. Also, documenting your test results and presenting them to the lab improves your credibility and keeps them on their toes. Even the best labs occasionally provide faulty equipment.
2) Minimize the lengths of soft tubing by butting up the harder tubing or hardware against each other as close as possible. We find compression fittings more likely to leak, not less.
3) Avoid incompetent labs if you have a choice.
4) Collect an adequate number of samples to evaluate spatial heterogeneity. This may be the most important part. At least when working near sources, we’ve repeatedly found that the primary source isn’t where we expected it to be, and our best guess would have provided concentrations that are orders of magnitude lower than maximum. The only solution is to drill lots of holes, which is practical with the Vapor Pin®. I’ve personally installed as many as 56 in a day, and my younger coworkers have hit 90. In many cases you can screen them with a PID and collect a select few for lab analysis.
Please refer to our White Papers under resources for additional information. One with the Michigan DEQ in which we installed four Vapor Pin® next to their “conventional” sub-slab points (Swagelok fittings set in cement). They used a variety of labs, sample containers, and analytical methods over the course of months. But any way we cut it, when we plot the Vapor Pin® against conventional points, we get a good correlation. The second white paper was done in conjunction with H&P labs in San Diego. Their sub-slab points, as described in the CA guidance, amount to miniature monitor wells, complete with sand packs and screens. They collected 10 sample pairs, and again, the correlation is excellent. In spite of all the issues concerning the Silicone sleeves, the Tygon used to make connections, and others issues we haven’t touched on, the fact that we get the same results over a broad range of concentrations and compounds proves that the Vapor Pins® does what it’s designed to do.