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Tuesday, April 12, 2016

CASAA: Vaping On a Plane...

From the "Call to Action"
[I am writing this in part because of the juxtaposition of being hammered in the CASAA Facebook forum for complaining about a commercial vaping ban while in the very same thread reading this call to action... but more on this in another post.  The other part of this is based on some conversations with vaperatti regarding how the vaping industry is ignoring the dangers of lithium ion batteries.]

In the link and image to the right we see CASAA pursuing the notion that, basically, vapes on planes are okay.

So let’s take a look at the technical aspects of this.

First off, as background I have spent the last several years involved professionally with the use of these very same types of batteries and corresponding electrical and software systems.  My background is in both electronics and software with a total of more than forty years of professional experience.

For part (a few years ago) of this I worked on the PrimusZ mod - a wireless bluetooth 60W box mod.  I also work professionally in other industries with these same batteries in a similar capacity.

I have designed and built successful charging systems as well as high output systems power systems (600W).

I have also been involved in vape shops and vaping both in retail and wholesale for the last several years.

Say what you want, criticize, make fun and laugh if you will but I know my around these types of batteries and the systems that use them (basically I’ve insured myself without a claim, designed built and sold systems (often to people who didn't possess the ability to understand what they were doing) without incident over the last several years - both on my own and with others in various organizations).

What follows is the short background of vaping, batteries and mods so that we can get to the real issue…

#1 - Vaping is very different than most lithium ion battery applications.  Why?  For one, generally these devices are looking to discharge the batteries at their maximal rate irrespective of battery safety while being fired.  In general most other types of systems are looking to have a longer-term, low rate battery discharge, e.g., a flashlight or robot.

Batteries are typically rated with a “C” indicating the maximum safe discharge rate for the battery - safe being the operative word here.  Typically this rating is something provided by a manufacturer.  

Vaping, particularly mechanical mods, basically looks to discharge a battery into the smallest possible load (very low ohms) in order to create the maximum amount of heat and hence vapor.  Typical coils may be rated at a .2 ohm value or less.

Ohms law says current (amps) is proportional to volts divided by ohms.  Thus a 7.2V dual 18650 battery set up yields about 36 amps into a .2 ohm load.  Watts, which is volts time amps, represents the apparent electrical power of a given circuit.  In this example 7.2 V x 36 amps = 259.2 watts.

A typical high powered LED (light emitting diode) application, as comparison, might consume one (1) amp for the same 7.2V and represents about 7.2 watts of power.

The difference here is that the LED device will burn much, much longer than the vape - less load, longer life.  This is because in this example the batteries are draining roughly 36 times slower for the LED application.

#2 - Lithium ion batteries are sensitive to discharge rate and temperature.  If I use a much lower ohm coil value, say  .05 ohms, I enter the territory where the battery is effectively shorted.  When this happens the batteries can do any number of bad things such as burn, explode, vent or over heat.  Similarly, heating a lithium ion battery above about 60C creates a similar internal state to a short - also resulting in a potential fire.

Batteries in a sealed compartment, e.g., mechanical mod, face a compounding of these problems.  The venting may increase pressure and temperature in the enclosed space of the mod's metal jacket creating a cascade of heating, additional venting,  and more pressure which in turn generates more heating, etc.

#3 - Most commercial mods have flawed or no safety systems.

In general all mechanical mods, from a battery perspective, are outright dangerous.  The reasons for this are many fold:  poor or no safety mechanism to prevent accidental discharge, non-vented tubes to hold batteries, and cases which efficiently transfer heat from the atomizer directly to the battery.

“Series” and “parallel” box mods with direct wiring and/or a MOSFET-style switch are basically the same as mechanicals in terms of battery safety with the possible exception of nonmetallic cases (which can melt instead of explode).

Neither mechanical or box mods generally support “short circuit” protection.

Most “closed” systems such as a Tesla Spyder or “Ego-type” battery rely on a sequence of button presses to turn the unit on and off.  In fact, the unit is always “on” and just draws a few micro amps (1/100,000ths of a amp) while waiting for you to pretend to turn it on.  The button pressing merely enables the devices ability to actually fire an atomizer.  Some of these systems can shut off on their own - but not all do.

Modern manufactured box mods typically have safety systems to prevent dead shorts for destroying the mod.  Those with internal computer chips typically support a sequence of button presses to turn the device on and off.

In general if you want to ensure a mod is actually powered off you must physically remove the batteries.

Most importantly nearly all mods require some active steps on the part of the user to ensure they cannot firing.  Usually by removing the atomizer and/or batteries.  In general users “forget” these steps.  Nearly every vaper I know has had, at least once, an bad mod/battery experience regardless of how careful they might be: smoking purse, smoking car, melting box mod, etc.

“Naked” 18650-style batteries can also be shorted out by metallic objects such as keys in a purse or pocket.

There are classes of batteries with safety systems to prevent shorts and fires but in general these are not favored by moders and vapers because the safety devices limit the power of the batteries.

#4 - Stored Energy 

So if you check wikipedia you will see that lithium ion batteries rate about equal to wood in terms of stored energy - gasoline, on the other hand, stores about fifty times more energy.

Wood's not dangerous?  So why are vape batteries?

Because the entire quantity of energy in the battery can be discharged in a very short time.  If you through an equal amount of wood into a very hot fire its energy will also be expended quickly - but only if you through it into a fire.  On its own or touching your keys in your pocket or purse it won't do anything - and that's the critical difference.

So what’s the bottom line?

Lithium ion batteries as used in vaping are, for the most part, accidents waiting to happen.  Items in a purse push the fire button on the Tesla Spider and the atomizer turns on and stays on until smoke starts coming out of the purse.  A mechanical thrown careless on a car seat turns on and burns the fabric. And so on…

My guess is that vapers, being former smokers, have an innate feel for things “catching fire.”  Certainly I do - my wife smoked for 40 years through four children - so you tend to catch things before they become problems.

Unfortunately, though, nothing I wrote above gives me or many others in the world faith that vaping devices and batteries are “safe” in the context of something like an airplane cargo compartment.

On the commercial side there are various processes and standards for lithium ion battery testing and safety.  Large shipping companies (like a UPS) have no problem shipping commercially certified batteries because such batteries have been reasonably tested to ensure A) there won’t be any accidental firing and B) are generally handled by a professional who knows to pack the batteries the right way, i.e., out of the device.  Generally batteries are removed from devices for shipping save for cell phones - in the case of cell phones enormous amounts of QA and testing address the general safety issue.

This is not true as far as any vaping devices I know of are concerned (except for some 18650-style mods).

So let’s now think about this from a safety perspective and not a vaping perspective.

If “Joe Random” puts his e-cig or mod in his checked baggage there is a significant chance that this device could fire unexpectedly - whether through jostling, vibration, coincidence, etc.  (This of course excludes physical damage during luggage handling, etc. which adds a whole additional dimension of potential problems.)

My professional view is that uncontrolled packing of vaping devices in airline, or for that matter any form of closed shipping container, luggage, baggage, container, or cargo hold is a very, very bad idea from the perspective of human safety.

When we built the PrimusZ - a system with two internal lithium ion batteries - we provided a mechanical pin/switch combination that physically disconnected the batteries from the rest of the device via a mechanical switch during shipping (remember, I am paying the insurance bills).  We shipped a few hundred around the country without incident.  Similarly, we never shipped a PrimusZ with an attached atomizer because we knew better.

All this for exactly the reasons outlined above: safety.

Can vaping devices be shipped safely?

In checked baggage where we rely on the “user” to do the right thing, i.e., pack it safely, I would say absolutely not.  I have seen far to many “near misses” in cars much less areas where a mistake would cause significant danger.

(This is not to say someone knowledgable couldn’t make things safe: removing batteries and placing them in “battery protector” separated from all metal, removing the atomizer, etc.)

Long ago I worked on flight systems and when you are involved with things like that you take safety far more seriously than your average vaper - particularly when you start to think about what might happen to your family if you make a mistake on the safety side and your family is riding on that plane.

Personally I don’t have a problem with empty (as in no batteries) mechanicals or box mods in checked baggage provided there is an independent (for example, a scanner at the airport) safety check to ensure that there are no batteries present in the baggage.  All batteries should, I think, be allowed in carry on where any evidence of smoke or heat can easily be detected and TSA folks can ensure they are package safely - that is on the floor and not in the overhead compartments.

But again, can we rely on “Joe Random” to take this seriously?

I doubt it.

So, at least in my professional opinion, this “Call to Action” is a very, very bad idea.

Safety in the sense of a battery fire on an airplane, ship or train is a far different matter than somebody annoying someone with their vape or “disrespecting” their right to ban them.

Given what I know I wouldn't want to be on a airplane with one these things in the cargo hold - not me, not my family, and not you.

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