ppm calculation

[LucidDreamer]

Some neo-nazi has claimed that I miscalculated. Can one of you guys check this to make sure I did not make an error?

 

His calculation.

 

According to the Merck Index, dozens of conversion tables and as many online sources that I could find I have come to the conclusion that Zyklon B (Hydrogen Cyanide or HCN) was sold in tins that containd 1.134kg of HCN. According to the Merck Index, above 25 degrees celsius HCN readily forms the gas. According to the Merck and other sources, the lethal concentration of Zyklon B or HCN needed to kill within minutes is 300 parts per million (ppm) which is in fact 300mg per liter of air and because of its vapor pressure, it can easily attain this.The shipments of Zyklon B to Auschwitz/Birkenau were 7.5 tons (1942), 12 tons (1943) and 6 tons (1944) for a total of 25.5 tons of Zyklon B (HCN).I found a few sources but it seems the Dachau gas chamber was 24'x18'x6' and others were about the same being 20'x20'x6'. Using the smaller (which is not in a revisionist's favor), you get 2400 cubic feet which translates to 67968 liters of air in each gas chamber. In a 20'x20' room, an extremely generous estimate of 400 people, that is 1 person per square foot would be the max that could fit. The volume of 400 people that are about 70kg average would be about 50L per person, thus 50L x 400 = 20 000L, so now the total room air volume is 67968-20000 = 47968 Liters. In order to obtain the 300ppm to kill people, for the 47968L number would be 14.39kg of Zyklon B. 14390000mg/47968L = 300ppm. So now we have 14.39kg per gassing. If 1 ton = 907.185kg, then there are 50.4 gassing per ton of Zyklon B, for a total for 25.5 tons of 1285.2 gassings. Thus using the very generous number of people I have given of 400 people per gassing x 1285.2 gassings = 514080 people gassed. NOT 1 MILLION and definately not 4 million. If we were to be realistic, the 400 people would be brought down to 180-200 per gassing giving only 231336-257040 people.Which again shows their numbers don't add up and the whole thing is fabricated and a lie.

 

My calculation:

 

You have made a critical error in your calculation. I have indicated the error in bold. You have used a calculation for parts per million that only applies to water. The reason this calculation works for water is because one millimeter of water weighs one gram. It doesn’t work for any other milligram/litter parts per million calculations because the solute doesn’t weigh 1 gram per millimeter, including air. The parts per million to mg/m cubed is represented by this equation:

C (mg/m3) = C (PPM) x MW / 24.45. So if I have 300 PPM I multiply x the molecular weight of HCN which is 27.081 then divide by 24.45. This gives me 332.28 mg/ m cubed. Given that there are 1000 liters per m cubed there would be .3322 mg/liter of HCN to give an exposure of 300 PPM. Assuming that you have not made any more errors and taking your value of 47,968 Litters for the amount of space to be filled it would require 15,939 milligrams for 300 parts per million. This is only 15.93 grams and .0159 kgs. Again, using your value of 200 people per gassing and 25.5 tons of zyklon b that would be enough gas to kill 326 million people.

 

Thanks in advance. I know this is a tedious calculation.

[Skye]

You're correct in saying 300 ppm in air isn't equivalent to 300 mg/L, it's a weight-weight ratio of 1:1,000,000.

 

This is how I'd calculate it, in simple steps because I'm tired.

 

I'll assume 1 liter of air to weigh 1.25 grams.

 

We have 47,968 liters of air

 

So this weighs 59,960 grams (47968 x 1.25).

 

To find the weight of substance at 1 ppm we would simply divide by 1,000,000 to get 0.05996 grams.

 

Multiply this by 300 to get 300 ppm, equals 17.988 grams.

 

That is the total weight required to give 300 ppm in the 47,968 L room.