We do have a product that Desco recommends for field service work when an AC outlet (equipment ground) is available. The problem is that for grounding to work, the AC outlet needs to be wired correctly (hot, neutral, and ground). Improper wiring more frequently occurs with drop down cords and power strips; we have seldom seen the problem with wall outlets. So Desco recommends a Desco 98130 AC Outlet Analyzer and Wrist Strap Tester. An LED illuminates if the wiring is correct.