Friday, September 28, 2012

The Nexus Shooting Difference - Part 1 - Range ventilation

We will be writing a multi-article post describing features of Nexus Shooting that will set us apart from the typical shooting range.  For this first article, let's discuss the important topic of range ventilation.

Lead poisoning is a very real problem with many shooting ranges.  The Center for Disease Control / National Institue for Occupational Safety and Health (CDC/NIOSH) has published the following guidelines for preventing occupational lead exposure which also includes many case reports of lead poisoning from shooting.  Feel free to peruse their recommendations and the case reports by clicking this link:  http://www.cdc.gov/niosh/docs/2009-136/pdfs/2009-136.pdf

Lead poisoning can induce nausea, vomiting, headache, high blood pressure, abdominal pain, memory and mood disorders, and alter fertility.  Because of these significant effects, lead levels of shooting range employees are very strictly regulated.  Have you ever seen any of the employees at a range wearing one of these?

 
It is because their blood lead levels tested abnormally higher than allowed!   Fortunately, they have the good sense to follow the recommended testing and prescribed intervention.  But, these guidelines are for EMPLOYEES of ranges.  Where are the guidelines for CUSTOMERS of gun ranges?  THERE ARE NONE!

Besides lead, there are all sorts of different byproducts of shooting which can be inhaled.  Carbon monoxide, gunpowder, smoke, etc.  Below is an actual picture of a standard N95 filter mask (in front)that has turned visibly grey after shooting 100 rounds in a poorly ventilated range (a new clean filter is in back for comparison).  Clearly, this is garbage that you do not want to inhale!


So, how is a ventilation system designed to prevent inhaling all of these shooting byproducts and help reduce the chance of lead poisoning?  The recommendations by the CDC/NIOSH state "Perforated radial air diffusers mounted at ceiling height have been tested and demonstrated effective in meeting established industry and regulatory air flow criteria.  Diffusers that produce jets of air can create turbulence at the firing line." - page 14 of  guidelines for preventing lead exposure

This diagram shows ceiling air diffusers which draw outside hot air in and  produce swirling air and turbulence.  Clearly, this is ineffective at properly ventilating the range.  Additionally, the introduction of jets of cold air from standard air conditioning vents disrupts air flow, causes turbulence, and is only minimally successful at producing "warm" air.  Even worse, some ranges only turn on the ventilation sporadically to save on energy costs!
 
 
 
 
 
 
The diagram below shows what optimum airflow from a radial diffuser looks like.  The air moves as a single mass, all in a downrange manner, in a laminar fashion with NO turbulence at 75 feet per second.  The ventilation system should be on the whole time.
 
 
The above radial diffuser works great at ventilation, but the problem with the this setup is that it draws its supply from the hot humid outside air.   Some ranges try to band-aid fix this by introducing those same standard air conditioning vents which cause jets of air, disrupt the laminar airflow, and result in turbulent warm air as shown below.  With this type of system you are back to square one with a poorly ventilated sauna!




The best way to obtain the combination of great ventilation AND ice cold air is to cool ALL of the air coming out of the radial diffuser while recirculating a portion of the cold air through multiple layers of HEPA filtration as shown below.  Obviously, this is the ideal situation to have at an indoor shooting range.  So, why don't all ranges use this system?   Because it costs about FIVE TIMES more in just the capital costs of the equipment alone and cooling the entire volume of air sends the electric bill through the roof!  But, because we are committed to providing the best shooting environment possible, we are installing this ventilation system, which literally costs $1 million!  This is the same exact system used in many military and law enforcement indoor ranges.


As a medical doctor, I am acutely aware of the numerous health risks present in most pre-existing shooting ranges. At Nexus Shooting, if we can provide the healthiest and safest environment for shooters, we can sleep easy at night knowing that we care about our customers and are not just trying to maximize the bottom line.  

- Dr. Bernard Hsiao, MD. Ph.D, co-owner of Nexus Shooting.

 
 






4 comments:

  1. I beyond doubt appreciate your articles and blogsst7

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  2. I just came from Nexus for the first time. I'm only a medical student, but the particulates were a concern for me. After shooting for about an hour, I realized I didn't once smell gunpowder. At that point, I had brought my paper target in and quickly looked to see if it was moving in an air current. There was no movement of the light paper target. I was very impressed by the fact that there was no apparent current yet the area was very obviously well ventilated. This was just one of the many things that impressed me about Nexus today.

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    1. Glad you noticed, Eddy! Thanks for your kind comments and for coming in!

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