The Design Institute for Emergency Relief Systems (DIERS) Users Group has a membership of over 130 companies worldwide. It is an affiliate of the American Institute of Chemical Engineers. Its primary mission is to advance the technology and practice in the design of emergency relief systems for runaway reactions. This proposed survey is primarily on runaway reactions while recognizing there are many other venting applications of interes.

The purpose of the survey is to benchmark various runaway risk reduction methods used from a risk and cost-benefit basis. It will also promote the consistent use of the DIERS and other venting technologies in risk assessmen.

Since it was first proposed by DIERS in March 1997, the survey has received much interest, not only from various international process safety, chemical engineering, and chemistry associations, but also from many non-chemical associations worldwide. The survey is expected to be sent this year.

This paper outlines the background, purpose and procedure of the proposed survey; why DIERS should be used and why it is apparently used inconsistently; the benefits of larger vents and higher vessel design pressures and the theme of the survey questions.

Many of the broader issues of risk assessment were addressed in the 1994 DIERS Report, “Risk Consideration for Runaway Reactions,” Appendix 1 entitled “Addressing Some Issues Faced in Runaway Risk Assessment” [l].