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How do I measure Brown’s Gas Production?

Do I need to make an elaborate volume test apparatus like you show in ER_VolumeTestApparatus.doc in order to measure gas production?
No, that’s overkill for what you need.  The VTA allows you to take reasonably accurate measurements without assistance.  
You can get reasonably accurate gas volume by timing the filling of a pop bottle underwater, IF you do it correctly.
NOTE: Beware of tests:1. Like this one, because the weight of the bottle isn’t accounted for (the bottle weight is pressurizing the gas), so there is actually MORE gas production than ‘indicated’.2. Like this one, that pushes the hose deep underwater, (because the electrolyzer builds pressure when the hose is that deep.  The ‘extra’ pressure/gas is then released when the bottle is at ‘ambient’ pressure), so there is LESS gas than ‘indicated’.
You’ll need an assistant, a stopwatch, a couple of containers, a pen and paper.
1. Find an appropriate sized bottle.  For an ER50 I’d use one that is about 0.5 liter in volume. 
2. Carefully measure the EXACT volume of the bottle, (in mL or cc).  Use a measuring cup, graduated beaker or syringe to find the exact volume of the bottle by measuring the water it takes to fill it (it’ll be more than the stated volume on the side of the bottle). 
3. Find a bucket large enough to easily fill the bottle with water and turn the bottle upside down.
4. Fill the bucket with warm (room temperature) water; so your hands don’t get cold while holding them submerged and the gas can be at Standard Ambient Temperature and Pressure (SATP).
5. Start your electrolyzer and let it warm up (it will be more efficient at higher temperature).
6. Have an assistant stand by to operate a stopwatch (an iPhone app works fine) and take notes on paper (I prefer to make a chart like a spreadsheet).
7. Submerge the bottle in the bucket and allow it to fill with water.
8. Turn the bottle upside down so that the opening is down and raise it out of the water so that the opening is only about 1 inch submerged (the water will stay in the bottle).
9. Make sure the electrolyzer won’t shut off during the duration of the test, (reset the timer if needed).
10. Submerge the gas hose under the water about 1 inch and wait for the bubbles to stabilize (about 5 seconds should do it for an ER50).  The deeper you go, the more pressure the ER50 would need to build (which is ‘gas storage’) which would skew your ‘volume’ results.  You need to have the electrolyzer gas pressure as near ambient as possible for most accurate results.
11. Raise the bottle about 1/2″ (do NOT lift it out of the water) and insert the gas hose under it (so bubbles now enter the bottle)… At the SAME TIME have your assistant start the stopwatch.Water will now come out of the bottle as gas goes in.
12. Keep timing until the gas completely fills the bottle, then stop the stopwatch.
Write down the results.  It’s best if your assistant does this as your hands will be wet.
Now you have a volume and a time.  So lets do the math.
You are looking for volume/time.  Scientific Standard is Liters per Hour (L/hr)
1 hour is 3600 seconds.  Volume is in liter (1000 ml or 1000 cc)
For comparison, if the electrolyzer filled a 1 liter bottle in one minute (60 seconds) you’d have a gas production of 60 L/hr.  Less time is more L/hr.  More time is less L/hr.
So an ER50 (rated to produce at least 50 liters of BG in an hour) should fill a 0.5 liter bottle in just over 36 seconds.
The actual math looks like this:
3600 (seconds in an hour) / 50 liters = 72 seconds to fill a 1 liter bottle.  72 (seconds)  * 0.5 (volume of bottle) = 36 seconds 
So in an actual experiment, if it took 50 seconds to fill a 0.5 liter bottle you’d find the liters / hour with this formula:
(3600 / seconds recorded) * 0.5 (volume of bottle in liters) = 
(3600 / 50) * 0.5 = 36 liters per hour. 

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