Purpose
The purpose of this ballot is procure group direction moving forward with the discussion concerning the use of the DIM versus the Secondary method for measuring airflow in Standard 49.
Background
Issue paper BSC-2013-04 highlighted the need for updating the current rules for using the DIM versus circumstances where an alternate method may be used for measuring inflow. The proponent contends that occasionally it has been observed that a recertificaion has been performed very close in time proximity to a previous certification, using a different inflow method, and the hood will pass one method but not the other. This calls into question the validity and comparability of the various methods.
During the 2014 JC Face to Face meeting, the topic was presented, discussed and ultimately the JC agreed to establish a Task Group to gather data and discuss this topic in greater detail.
Since that time, the task group has met a total of five times. Task group members have independently gathered data comparing methods with highly suspect results. Although the group generally agreed the secondary method adopted in the 2002 publication of Standard 49 should be removed, during the latest teleconference it was alternatately proposed to first ask the entire JC the following question:
Regarding the use of the Secondary method described in Standard 49, which of the following courses of action should the JC pursue?:
1) Leave the current method in, as is; or
2) Remove the secondary method from the standard entirely; or
3) Develop language allowing the possibility of using a secondary method, but require the manufacturer supply a statistically usable and provable secondary method
In this straw ballot, please select the one best answer that describes your position. Comments are not obligiatory, but welcome.
The Task Group will use the results of this to determine steps moving forward. |
