"I just celebrated my 30th year in the valve sealing industry and I realize I was very lucky to see the world change in regards to fugitive emissions in valves. Back in 1990 when I started, a valve was not considered to be leaking unless it measured a leak rate of over 10,000 PPM. Today, this type of leak rate would be a serious issue needing immediate attention. Thirty years later, it is common to see 100 PPM limits and even 50 PPM in some places. How big of a change is 10,000 PPM to 100 PPM?"
Read the Valve World Americas article written by Ron Frisard, A.W. Chesterton Company, here: https://www.valve-world-americas.com/webarticles/2021/05/14/in-the-room-where-it-happened-with-fugitive-emissions.html