wider snorkel tube ?

[ryan65]

hi i was wondering if there are different widths of snorkels. i feel.the standard size doesnt let me take the deepest breadth possible before a dive.
would appreciate some info. are there different sizes, what are the pros and cons etc

 

[DRW]

National and international standards and rules prescribing breathing tube dimensions have changed over time:

The table above illustrates how these measurements have shifted in response to better understanding of the effects of dead space and breathing resistance on carbon dioxide retention:

• Maximum tube length has almost halved (from 600 to 380 mm).
• Maximum bore (inner diameter) has increased (from 18 to 25 mm).
• Capacity (or inner volume) has partly replaced inner diameter when dimensioning snorkels.
• Different snorkel dimension limits have evolved for different users (first specified as adults/children; then taller/shorter heights; then larger/smaller lung capacities, all of them used as proxies for expected tidal volume, as the ratio of tidal volume to dead space controls the amount of carbon dioxide in the inhaled air of each breath).

 

[ryan65]

wow thats great info. thanks for thw details

 

[Bill McIntyre]

I had no idea that these standards for snorkels existed. Other than a few which seemed pointed at competitive events are they mandatory or just recommendations? Do they dictate what can be sold in those countries? What can be used in those countries? For instance those that specify what can be used for smaller or larger lung capacities surely must be just advisory unless users must have their lung capacities measured. I have no idea whether the Riffe Stable snorkel that I used for years complies with some standard. It has that accordion feature that lets the mouthpiece fall away from my mouth. There is no mention of that in the standards. Is it OK?

 

[DRW]

I had no idea that these standards for snorkels existed. Other than a few which seemed pointed at competitive events are they mandatory or just recommendations? Do they dictate what can be sold in those countries? What can be used in those countries? For instance those that specify what can be used for smaller or larger lung capacities surely must be just advisory unless users must have their lung capacities measured. I have no idea whether the Riffe Stable snorkel that I used for years complies with some standard. It has that accordion feature that lets the mouthpiece fall away from my mouth. There is no mention of that in the standards. Is it OK?

National and international standards exist for many items of diving equipment, including masks, fins, snorkels, breathing apparatus, drysuits and wetsuits.

In the matter of snorkels, here is an example of British Standard compliance from the 1970s:

The manufacturer claimed that all the breathing tubes illustrated above complied with British Standard 4532 except for the flexible-hose model at the bottom of the page. British Standard 4532 (Specification for Snorkels and Face Masks), front page below, did not mention flexible-hose snorkels specifically:

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More anon. Incidentally, such Standards did not confine their content to dimensioning. They often laid down quality testing procedures and usage safety rules.

 

[ryan65]

hi,
thanks again foe the details
what are the pros and cons of having a flexible hose mouthpiece ,for freediving?

 

[ryan65]

and another question,
the standartization of snorkels. is this just a safety issue or also a efficiency issue as well. I mean as a freediver i want the most efficient snorkel that will give me the best breadth. would a wider snorkel be better or are the standards considered optimal after research.?
thanks

 

[DRW]

hi,
thanks again foe the details
what are the pros and cons of having a flexible hose mouthpiece ,for freediving?

The co-founder of Scubapro Dick Bonin is credited with the introduction of the flexible-hose snorkel in the mid-1950s.

Flexible-hose snorkels are preferred by some scuba divers because the flexible hose between the tube and the mouthpiece causes the lower part of the snorkel to drop out of the way of the demand valve when it is not in use. The hose will bend to any shape or angle and any residual water will run out when the snorkel hangs out of use at the surface. The flexible design eliminates "jaw pull" if the barrel ever snags on an underwater object.

However, a freediver or spearfisherman equipped with this snorkel design must have a hand free to replace the mouthpiece when it falls out of the mouth. The corrugated hose must also be non-kinking to secure the air supply.

I have often snorkelled with flexible-hose breathing tubes and have found them satisfactory in use.

 

[DRW]

and another question,
the standartization of snorkels. is this just a safety issue or also a efficiency issue as well. I mean as a freediver i want the most efficient snorkel that will give me the best breadth. would a wider snorkel be better or are the standards considered optimal after research.?
thanks

Treat national Standards as quality marks for consumer products. They are not mandatory on all manufacturers, but any complying with these Standards may be favoured by risk-aware consumers. The publication of British Standard BS 4532 in 1969 arose from concern for user safety, particularly that of vulnerable underwater swimmers such as children with less developed lung capacity than adults.

Finding the best freediving snorkel for one individual will always entail some trial and error on that individual's part. Skin Diver magazine published the following snorkel roundup in 1980:

​

You might discover similar comparative snorkel data online or in print if you do the research. There are no instant answers.