Quality Carbon Monoxide Detectors for Scuba Cylinders

[bpodbielski]

Haven't seen anyone recommend this one yet, but take a look at OxyCheq Expediton CO analyzer.

This comparison was interesting for me:

CO Analyzer Comparison​
​	OxyCheq Expedition CO​	Analox EII CO​
Price​	$400 MSRP​	$355 MSRP​
Replacement Sensor​	$140.00 MSRP​	$240 to $250 (MSRP / Exchange rate)​
Alarm​	Sounds @ 10 PPM +/-1 PPM​	No Alarm​
Measurement Range​	0-100 PPM​	1-50 PPM​
Sensor Life​	3.5 + Years​	2 years​
Sensor Accuracy​	+/- (1% FS + 1% value)​	+/- (1% FS + 5% value)​
Sensor Drift​	Less than 0.5 ppm Annually​	6.0 ppm Annually​
Calibration*​	When New Sensor Installed or 3.5 years.​	Every time used – Prior to every dive with Bump Test​
Hydrophobic Membrane​	Yes​	No (None Noted)​
Bump Test Required for Calibration​	No​	Yes ($80 USD) Valid for only 20 Bump test (uses)​
Temperature Compensated​	Yes​	No (Not noted or found)​
Power​	3 ea AAA​	1 ea 9V​
Battery Replacement​	2-3 years (Occasional Use) 1 year (Inline Compressor Use)​	1 year​
Display​	3 Digits​	2 Digits​
Warranty (Sensor)​	1 year (prorated)​	1 year (prorated)​
Hand Held​	Yes​	Yes​
Compressor Inline Use​	Yes​	No​
Continuous Use​	Yes​	No​
Flow Restrictor (s)​	Yes (Optional / Recommended)​	No (No Options)​
Purchase price​	Analyzer $400 (MSRP) w/ Case Optional Restrictor: $40.00 Total: $440.00​	Analyzer: $355.00 (MSRP) (No Case) Bump Tester: $80.00 (20 dives) Total: $435.00​
1 Year Expense​	None​	Bump Tester: $80 (20 dives) Battery: $1.50 - $3​
2 Year Expense​	Batteries $2 - $4​	Sensor: $240.00 Bump Tester: $80.00 (20 dives) Battery: $1.50 - $3​
3 Year Expense​	None​	Bump Tester: $80 (20 dives) Battery: $1.50 - $3​
4 Year Expense​	Sensor $140.00 (3.5 – 4 years) Calibration: ~ $55 Batteries $2 - $4​	Sensor: $240.00 Bump Tester: $80.00 (20 dives) Battery: $1.50 - $3​
Total Cost Over 4 years​	$600.00 (w/o Flow Restrictor) Does not include batteries ($4 - $8)​	$1235.00 Does not include batteries ($6 - $12)​

Cave Adventurers - OxyCheq Expedition Carbon Monoxide Analyzer w/ Alarm - Marianna, Florida USA - Never Undersold!

OxyCheq Expedition Carbon Monoxide Analyzer w/ Alarm

www.caveadventurers.com

 

[BoltSnap]

Haven't seen anyone recommend this one yet, but take a look at OxyCheq Expediton CO analyzer.

This comparison was interesting for me:

​

CO Analyzer Comparison​
​	OxyCheq Expedition CO​	Analox EII CO​
Price​	$400 MSRP​	$355 MSRP​
Replacement Sensor​	$140.00 MSRP​	$240 to $250 (MSRP / Exchange rate)​
Alarm​	Sounds @ 10 PPM +/-1 PPM​	No Alarm​
Measurement Range​	0-100 PPM​	1-50 PPM​
Sensor Life​	3.5 + Years​	2 years​
Sensor Accuracy​	+/- (1% FS + 1% value)​	+/- (1% FS + 5% value)​
Sensor Drift​	Less than 0.5 ppm Annually​	6.0 ppm Annually​
Calibration*​	When New Sensor Installed or 3.5 years.​	Every time used – Prior to every dive with Bump Test​
Hydrophobic Membrane​	Yes​	No (None Noted)​
Bump Test Required for Calibration​	No​	Yes ($80 USD) Valid for only 20 Bump test (uses)​
Temperature Compensated​	Yes​	No (Not noted or found)​
Power​	3 ea AAA​	1 ea 9V​
Battery Replacement​	2-3 years (Occasional Use) 1 year (Inline Compressor Use)​	1 year​
Display​	3 Digits​	2 Digits​
Warranty (Sensor)​	1 year (prorated)​	1 year (prorated)​
Hand Held​	Yes​	Yes​
Compressor Inline Use​	Yes​	No​
Continuous Use​	Yes​	No​
Flow Restrictor (s)​	Yes (Optional / Recommended)​	No (No Options)​
Purchase price​	Analyzer $400 (MSRP) w/ Case Optional Restrictor: $40.00 Total: $440.00​	Analyzer: $355.00 (MSRP) (No Case) Bump Tester: $80.00 (20 dives) Total: $435.00​
1 Year Expense​	None​	Bump Tester: $80 (20 dives) Battery: $1.50 - $3​
2 Year Expense​	Batteries $2 - $4​	Sensor: $240.00 Bump Tester: $80.00 (20 dives) Battery: $1.50 - $3​
3 Year Expense​	None​	Bump Tester: $80 (20 dives) Battery: $1.50 - $3​
4 Year Expense​	Sensor $140.00 (3.5 – 4 years) Calibration: ~ $55 Batteries $2 - $4​	Sensor: $240.00 Bump Tester: $80.00 (20 dives) Battery: $1.50 - $3​
Total Cost Over 4 years​	$600.00 (w/o Flow Restrictor) Does not include batteries ($4 - $8)​	$1235.00 Does not include batteries ($6 - $12)​

Cave Adventurers - OxyCheq Expedition Carbon Monoxide Analyzer w/ Alarm - Marianna, Florida USA - Never Undersold!

OxyCheq Expedition Carbon Monoxide Analyzer w/ Alarm

www.caveadventurers.com

This one has been out of stock for a very long time "DUE TO SUPPLY CHAIN ISSUES."

Expedition CO Analyzer w/ Alarm

Expedition Carbon Monoxide Analyzer with Alarm. Compact and fits in your hand Range: 0-100 ppm Accuracy: +/- 2 ppm Alarm: Alarm sounds @ 10 ppm (+/- 1ppm) Sensor: Galvanic (Replaceable) Cost to Replace Sensor: ($140 MSRP) Response Time: 95% @ 10 seconds (May very in extreme temperatures) Sensor...

www.oxycheq.com

 

[grf88]

I bought an Analox CO meter when they first introduced them but unfortunately they discontinued support and replacement sensors became exorbitant. It may very well have saved my son's life however when we discovered 80ppm in his tank on a dive trip. Since then I have used the Sensorcon and used the flow restrictor from the Analox with it. The Sensorcon is sensitive to flow and pressure but if it reads zero no need to check further. If it doesn't read zero then use the bag method.

 

[DandyDon]

Do we need to test every cylinder or just nitrox?

Every tank, otherwise you're gambling.

Where's @DandyDon? I'm surprised he hasn't chimed in here yet on this one.

Well, the thread is going well without me. I am a CO fanatic but not an expert.

Analox EII CO

Obsolete.

The Sensorcon is sensitive to flow and pressure

Yeah, that's why I use a gallon ziplock, the ones with the handles for easy closing. You still gotta avoid motor fumes.

 

[LFMarm]

I use this one (Carbon Monoxide Meter | USA NIST Calibration) fed with a DiveSoft flow limiter (Divesoft Professional Flow Limiter MK2 DIN G/58) that I also use for my trimix analyzer. You can replace the whole analyzer every 2 years for less than half the cost of a sensor from other manufacturers.

Even very small concentrations of CO can be fatal for deep CC dives. I have been checking every tank, including those for shallow OC dives, since getting the analyzer. Luckily all my readings have been <5 ppm so far (vast majority 0 ppm).

 

[LFMarm]

I recommend reading this article from DAN to anybody who questions the importance of CO analyzing: Carbon Monoxide Safety

Even small amounts at the surface can have very significant effects at depth. Here is the example for a gas with 10 ppm at the surface. It becomes high as of 30 m and dangerous as of 60 m.

 

[sujoe]

I use this one (Carbon Monoxide Meter | USA NIST Calibration) fed with a DiveSoft flow limiter (Divesoft Professional Flow Limiter MK2 DIN G/58) that I also use for my trimix analyzer. You can replace the whole analyzer every 2 years for less than half the cost of a sensor from other manufacturers.

Even very small concentrations of CO can be fatal for deep CC dives. I have been checking every tank, including those for shallow OC dives, since getting the analyzer. Luckily all my readings have been <5 ppm so far (vast majority 0 ppm).

I'm looking for the same setup too. Do you think this flow restrictor will work like the Divesoft Flow Limiter? Thanks in advance!

 

[LFMarm]

I'm looking for the same setup too. Do you think this flow restrictor will work like the Divesoft Flow Limiter? Thanks in advance!

I don't know the specs of this flow restrictor but will likely do the same job. The one from Divesoft provides a flow of 0.2 L/min which is optimal for the He sensor. I just started using a much simpler / cheaper / lighter flow limiter that just plugs into inflator hoses Flow limiter for an inflator - divesoft.com - Divesoft.com It also provides 0.2 L/min.

 

[sujoe]

I don't know the specs of this flow restrictor but will likely do the same job. The one from Divesoft provides a flow of 0.2 L/min which is optimal for the He sensor. I just started using a much simpler / cheaper / lighter flow limiter that just plugs into inflator hoses Flow limiter for an inflator - divesoft.com - Divesoft.com It also provides 0.2 L/min.

thanks! this is totally perfect!

 

[TNEngineer]

I saw the above Forensics Detectors review and thought at first it would duplicate mine. But given the description and price mentioned, it cannot be the one we recently purchased so I'll add a shorty review of my own.

Like others here, we have an O2 analyzer (Palm O2) which works great. Small, rugged, lightweight, ideal for dive travel. Been using it for years and just replaced its sensor ($100) so it's good for another 3-4 years. But that leaves open the question of CO contamination, particularly since virtually all of our diving is at remote locations where we don't know the equipment nor the people. So I went looking for a good CO analyzer.

Turns out Palm used to offer one, but everyone (including Palm!) says "out of stock and no known date". All of the eBay and Amazon options have minimum CO thresholds that are far too high for scuba. Finally, we found Forensics. Most of theirs are higher range too, but they have one specific model that is basically purpose-built for dive gas analysis (model "FD-103-CO-LOW", link here: Carbon Monoxide Super-Meter | 0.1 ppm | USA NIST Calibration)

Instead of the usual 1ppm or greater resolution, this unit goes down to 0.1ppm. It's IP67 rated and has good drop resistance. Perfect for bashing in your dive bag and then accidentally dropping in the rinse tank!

The price ($185 when we bought ours) is more than the eBay knockoffs but less than the Palm O2. They estimate three years of useful life before the sensor ages out. The only downside to this unit is the sensor is not replaceable. Oh well... even if you simply discard the old unit and buy a fresh one, $185/3 = $62 per year to know your gas is safe is darned cheap life insurance!

We have a small neoprene zipper/velcro pouch that holds our Palm O2 and its accessories. This unit slipped right into that same pouch, so now all of our gas analysis gear is in one padded place. We just toss it in the gear bag. We keep both analyzers in ziploc bags to protect their sensors from temp/humidity swings while in storage; supposedly this lengthens their useful life.

Highly recommended. Both for the product, and the fun/playful vibe you get from the company. They make great products and obviously love what they do.