If you want someone to blame, and if blaming someone will make you feel better, blame me. Here's the history:
Several years back NFPA 1127 was changed to cover drag races. The change was almost word for word what is in the rule now EXCEPT it was TWICE the complex distance for the total impulse. That then became the drag race safe distance rule for the Tripoli High Power Safety Code. That was too far for some so Tripoli's BOD came up with a special drag race rule for Research launches.
In September 2016 the NFPA Pyrotechnic Technical Committee, which includes rocketry codes, determined that the word "twice" probably should not have been included in the drag race rule. The committee (with Ken Good and me as representative and alternate) did an emergency TIA to change it. Ken/I voted for the change and the result is that the word "twice" will be removed from the current version as soon as it is approved by the Standards Council. If this sounds familiar it's because we explained it all before, in this thread, (https://www.tripoli.org/Forums/aft/386),">
https://www.tripoli.org/Forums/aft/386), where we announced the changes to the safety codes. Whit, you were very involved in the discussion.
Once it was approved by the Pyrotechnic Technical Committee, we (TRA BoD) felt we were safe adopting the new rule which cut in half the safe distances for our Tripoli High Power launches. I don't think there's any way we can be blamed for HATING drag races if we cut the drag race safe distances for commercial launches in half.
Then, because we still had that Research rule out there that was completely different, we tried to simplify things by adopting the same rule for our Tripoli Research Safety Code as the one for HPR.
It was all explained here:
https://www.tripoli.org/Forums/aft/386
Now before everyone gets too wound up, I urge you to do the calculations, using the impulse values you actually fly, and see what safe distance is really required. A 3K drag race with baby K motors could be done at 500 feet. Four 100% K motors can be done at 1000 feet. 10 K motors averaging 2000 Ns each can be launched at 1500 feet.
Then look at the old research rule and see what difference it makes if you're racing 3 or 30 K motors. Ask yourself, should the number of rockets make a difference?
Steve Shannon