{"product_id":"2940013459168","title":"Using Sulfur Hexafluoride as a Gaseous Tracer to Study Ventilation Systems in Mines","description":"The Bureau of Mines found sulfur hexafluoride (SF6), released from a lecture bottle, to be an ideal gaseous tracer for studying mine ventilation systems. Air samples were collected in glass syringes and analyzed by electron-capture gas chromatography. In these studies, the lower limit of detection was about 1 part per billion by volume (ppb) of SF6 per part of air. Experiments conducted in a Pennsylvania limestone mine showed this technique useful in evaluating the effectiveness of auxiliary fans, measuring low flow velocities, probing the air circulating near a working face region where ventilation appeared to be poor, and estimating volumetric flow rates in airways of large cross-sectional area and having low flow velocities. This technique was also used in a western vein-type metal mine to measure the amount of return air being recirculated into the intake air due to leakage through old stoped areas.","brand":"1001 Property Solutions LLC","offers":[{"title":"Default Title","offer_id":47145645113584,"sku":"2940013459168","price":2.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0737\/7593\/9824\/files\/2940013459168_p0.jpg?v=1763581764","url":"https:\/\/shop-qa.barnesandnoble.com\/products\/2940013459168","provider":"Barnes \u0026 Noble (DEV)","version":"1.0","type":"link"}