Scubaroo
Contributor
Hi all,
I know I've been asking lots of questions lately about nitrox, deep diving courses, etc etc. People are always saying "do a trimix course!" to which I think "but I won't be diving trimix for ages". Well I've been doing some snooping around on an Australian diving website, and some of the divers there have confirmed my worst fears about the cost of trimix diving in Australia. Here's a sample breakdown. The cylinder sizes are 7L deco bottles, and 12L 232bar doubles (approximately 55cf and 100cf). These are some of the more popular sized tanks available, mostly made by Faber - due to different cylinder standards, DOT cylinders such as Pressed Steel are not available down under. Also note that Australia uses metric measurements. Oxygen and Helium is sold by the litre in Australia, often with an additional airfill charge per tank. The formula used to calculate the gas charge is:
percentage x tank capacity(L) x pressure(bar) x gas price(c/L) x number of tanks
Scenario - set of 2 x 12L double tanks, trimix 30% O2, 30% He
single 7L deco tank of EAN50
Oxygen - 2c per litre
Helium - 6c per litre
Oxygen charge for doubles:
0.30 x 12 x 232 x 0.02 x 2 tanks = $33.40
Helium charge for doubles
0.30 x 12 x 232 x 0.06 x 2 tanks = $100.22
total cost for doubles = $133.62
Oxygen charge for deco:
0.50 x 7 x 232 x 0.02 = $16.24
So for a set of doubles full of trimix, and a bottle of EAN50, you're looking at a total of almost $150 just for the oxygen and helium. Plus the LDS might charge an additional $5 to $8 per tank for air! Add a tank of 100% O2 and you're looking at another $32-$40. It could easily cost $210 for a single dive's gas.
Conversely, a set of doubles filled with EAN32 (0.32 x 12 x 232 x 0.02 x 2) is about $35.65, plus maybe another $16 for air, which works out about $52 for the dive. There could also be an additional goods and services tax (GST) of 10% (similar to UK's VAT) on all of these prices.
I ran these prices past some Australian divers, and they said they're fairly representative.
I think I'll stick to Nitrox until I can afford a rebreather
I know I've been asking lots of questions lately about nitrox, deep diving courses, etc etc. People are always saying "do a trimix course!" to which I think "but I won't be diving trimix for ages". Well I've been doing some snooping around on an Australian diving website, and some of the divers there have confirmed my worst fears about the cost of trimix diving in Australia. Here's a sample breakdown. The cylinder sizes are 7L deco bottles, and 12L 232bar doubles (approximately 55cf and 100cf). These are some of the more popular sized tanks available, mostly made by Faber - due to different cylinder standards, DOT cylinders such as Pressed Steel are not available down under. Also note that Australia uses metric measurements. Oxygen and Helium is sold by the litre in Australia, often with an additional airfill charge per tank. The formula used to calculate the gas charge is:
percentage x tank capacity(L) x pressure(bar) x gas price(c/L) x number of tanks
Scenario - set of 2 x 12L double tanks, trimix 30% O2, 30% He
single 7L deco tank of EAN50
Oxygen - 2c per litre
Helium - 6c per litre
Oxygen charge for doubles:
0.30 x 12 x 232 x 0.02 x 2 tanks = $33.40
Helium charge for doubles
0.30 x 12 x 232 x 0.06 x 2 tanks = $100.22
total cost for doubles = $133.62
Oxygen charge for deco:
0.50 x 7 x 232 x 0.02 = $16.24
So for a set of doubles full of trimix, and a bottle of EAN50, you're looking at a total of almost $150 just for the oxygen and helium. Plus the LDS might charge an additional $5 to $8 per tank for air! Add a tank of 100% O2 and you're looking at another $32-$40. It could easily cost $210 for a single dive's gas.
Conversely, a set of doubles filled with EAN32 (0.32 x 12 x 232 x 0.02 x 2) is about $35.65, plus maybe another $16 for air, which works out about $52 for the dive. There could also be an additional goods and services tax (GST) of 10% (similar to UK's VAT) on all of these prices.
I ran these prices past some Australian divers, and they said they're fairly representative.
I think I'll stick to Nitrox until I can afford a rebreather