Scorkl Dangers
The Scuba Doctor doesn't recommend Scorkl devices because we think they're deadly dangerous. Here's why...
The Scorkl is sold as a shallow diving kit that lets you breathe freely under the surface with no bulky scuba equipment to get in the way of your exploring. No scuba certification required. The starter kit, which includes a hand pump, sells for around A$700.
The Scorkl is a 0.5 litre water capacity, 200 bar (2,900 psi) dive cylinder with a regulator and mouthpiece attached directly to the cylinder. It has a pressure gauge mounted on the mouthpiece which can be read without removing the device from your mouth. There is also the larger Scorkl Pro which holds up to 20% more air. If the Scorkl falls out of your mouth, your air supply is gone.
Safety Advice From Scorkl
There is a Safety Video for the Scorkl. It has plenty of warnings, many of which seem to come from the recommendations of scuba diving training agencies.
- General
- Use of the Scorkl is dangerous and can result in severe injury or death.
- The Scorkl does not meet the requirements of EN 250 and is designed for shallow diving use only. (Yet the founder, David Hallamore, claims the Scorkl is "certified to 6 metres" elsewhere.)
- Use only with these recommended limits:
- No deeper than 6 metres (20 feet). (The Scorkl doesn't come with a depth gauge.)
- Where the water temperature is above 15°C (60°F). (The Scorkl doesn't come with a temperate gauge.)
- Fitness To Dive
- The Scorkl is not suitable for use by children under the age of 10.
- Children under the age of 15 must be supervised by an adult that is trained in SCUBA. (Strange that adults using the Scorkl don't need scuba training, or supervision by someone trained in scuba.)
- You must be fit to dive to use the Scorkl.
- All users should consult with a diving doctor to determine whether they are fit to dive underwater.
- As a guide, if you answer YES to any of the questions below, you are UNFIT to dive, pending approval from a diving doctor. (The questions are taken from the forms typically used by the scuba training agencies for their medical declarations.)
- Swimming Guide
- You must be a proficient swimmer to use the Scorkl.
- Do not use the Scorkl if you cannot accomplish both of the following:
- Float or tread water for 10 minutes in deep water; and
- Swim continuously for 200 metres/yards (or 300 metres/yards swim with mask, fins and snorkel)
- Pulmonary Barotrauma — Burst Lungs
- Use of the Scorkl may result in pulmonary barotrauma ("lung over-expansion", "burst lungs", "exploded lungs")
- A diver who holds their breath underwater during ascent (i.e. moving towards the surface) risks pulmonary barotrauma
- Very small changes in pressure, even that which occurs over a metre (3 feet), can cause a pulmonary barotrauma
- All divers, regardless of depth, are at risk
- Pulmonary barotraumas have even been documented in swimming pools
- The three main reasons of pulmonary barotrauma are:
breath holding, rapid ascents and pre-existing lung conditions - To minimise the risk of pulmonary barotrauma:
- Never hold your breath while diving (breathe continuously). ESPECIALLY during ascent
- Never ascend rapidly (do not exceed an ascent rate of 6 metres (20 feet) per 40 seconds). (This matches the scuba diving recommendation of not exceeding an ascent rate of 10 metres per minute. But how is a Scorkl user supposed to do this without a depth gauge and timing device, or a dive computer?)
- Undergo a full medical exam by a doctor knowledgeable in diving medicine before using a Scorkl if you have a history of lung problems
- How to ascend safely:
- Maintain a normal breathing rate during a slow, controlled ascent
- Never hold your breath, especially during ascent
- In the event of an emergency ascent with breathing gas available, exhale throughout the ascent
- Ear Barotrauma — Burst Ear
- Use of the Scorkl may result in ear barotrauma
- An ear barotrauma occurs when a diver does not properly equalise the pressure in their ears with the surrounding water pressure
- The difference can occur by descending as little as 1–2 (3–6 feet) without equalising
- To minimise the risk of ear barotrauma:
- Equalise your ears before you feel pain or discomfort
- Equalise your ears first on the surface and then every metre (few feet) while descending
- Equalise your ears by blowing gently against pinched nostrils
- Do not equalise forcefully
- If experiencing pain, or having trouble equalising, ascend
- Decompression Sickness — The Bends
- Use of the Scorkl may result in decompression sickness
- Time underwater and depth are the key factors attributing to decompression sickness
- The relatively small volume of air available in Scorkl cylinders, compared to the large scuba cylinders, drastically limits these factors
- Decompression sickness is therefore only a remote risk for Scorkl users
- To minimise the risk of decompression sickness:
- Do not use the Scorkl below the 6 metre (20 feet) recommended depth. (The Scorkl doesn't come with a depth gauge.)
- Do not use more than 10 times in one day
- Be sure to rest at least 5 minutes between dives. (A bit hard to do when you're going to be spending a long time exerting yourself pumping up the Scorkl for the next dive.)
- Do not exceed an ascent rate of 6 metres (20 feet) per 40 seconds
- Air Quality
- Scorkl should only be used with clean, filtered, natural air (for example as per European Standard EN 12021:2014). (It's highly unlikely the supplied hand pump can deliver air that achieves this standard.)
- The Scorkl is not to be used with Nitrox (O2 content should be no greater than 21%)
- Safe Diving Practises
Strict adherence to the following safe diving practices is imperative for safe use of the Scorkl:- Ensure you are fit to dive
- Never dive with a Scorkl that shows signs of damage, leakage or substandard performance
- Never overfill the Scorkl system above 200 bar (3000 psi)
- Fit only Scorkl branded cylinders to the Scorkl regulator
- Test the operation of the regulator, purge button and pressure indicator before entering the water
- Check the pressure in the cylinder before submerging. Do not submerge if the pressure is below 50 bar (725 psi)
- Always dive with a buddy. Always stay close to your buddy.
- Equalise your ears during descent
- Never hold your breath (breathe continuously)
- Always begin ascent to surface with at least 50 bar (725 psi) remaining in the cylinder. (Scuba diving standards say you should finish your dive with 50 bar remaining in the cylinder.)
- Never deplete Scorkl entirely of air during a dive (as water may enter inner stages of the regulator)
- Never exceed an ascent rate of 6 metres (20 feet) per second
- Do not ascend to altitude or fly within 12 hours after diving
One wonders how many Scorkl users will view the safety video and fully understand the implications. This information is not published on the Scorkl web site as text, not even on their Safety page. No doubt it is repeated in the User Manual, but that is not downloadable from their web site either. At least you can now read the information here. There is a whole world of difference between viewing a safety video, or reading a user manual, and having the technicalities and dangers explained by a qualified scuba instructor.
What We Think About The Scorkl
As one commentator on the Kickstarter page put it, "This is a suicide device, wrapped up as a toy."
Here at The Scuba Doctor, we're not even comfortable with certified scuba divers using a Scorkl, let alone the target market of non-certified divers.
The Scorkl has a maximum depth limit of 6 metres (20 feet). It doesn't come with a depth gauge. How are people going to be able to use it safely?
The founder, David Hallamore, claims the Scorkl is "certified to 6 metres". The safety video says the Scorkl does not meet the requirements of EN250. So one wonders how it is actually certified, and how it could legally be sold in Europe where certification is required.
The recommended safe limit of 6 metres does not rule out the risk of lung over-expansion injuries. A rapid breath-hold ascent from 6 metres would almost guarantee that a user suffers a life-threatening rupture of the lungs.
The recommended maximum ascent rate matches the scuba diving recommendation of not exceeding an ascent rate of 10 metres per minute. But the Scorkl doesn't come with a depth gauge, dive watch, or dive computer. These are the tools used by scuba divers to carefully monitor their ascent rate. There is no way for Scorkl users to accurately judge their depth or ascent rate.
They claim the Scorkl sits weightlessly underneath your chin so you'll barely notice it as you swim. Well we get scuba divers complaining that a lightweight second stage regulator in their mouth produces too much jaw fatigue. A heavyweight Scorkl is not going to be nice and, if the Scorkl falls out of your mouth, your air supply is gone.
Does the Scorkl cylinder meet Australian certification standards? Does the valve/regulator have a burst disk? They don't tell the Scorkl users that scuba cylinders need to be visually inspected and pressure tested at a certified testing station once per year in order to comply with Australian Standards. See Scuba Cylinder Testing. The Scorkl is a scuba cylinder.
Filling The Scorkl Scuba Cylinder
A few different options are provided to fill the Scorkl's tank.
Filling Using The Scorkl Hand Pump
The Scorkl is available with what they refer to as a specially designed high-pressure hand pump to fill the Scorkl to 200 bar (3,000 psi). Well it's actually the same type of hand pump that's been on the market for many years to fill small paint ball cylinders. In that application, users don't care much about the quality of the air. The air is not going to be breathed by them.
The quality of the air breathed in by scuba divers is critical. Dive shops spend a lot of money on their compressors, the lubricants used in those compressors, the air filter on the compressor intake, the moisture removal system and the air filtration system to ensure high quality, breathable air. Sources of contamination include hydrocarbons from compressor lubricants, carbon monoxide (CO) from engine exhaust (or overheated compressor oil) and impurities from the surrounding environment such as methane and carbon dioxide (CO2). Dust particles in breathing gas can also be hazardous, potentially impairing respiratory function or damaging diving equipment. Excessive moisture can cause corrosion in scuba cylinders and other dive gear and may cause regulators to freeze due to adiabatic cooling (heat loss subsequent to increased gas volume).
The Scorkl hand pump comes with a replaceable air filter which is claimed to ensure Grade E scuba air quality. No details are given on the Scorkl web site as to how often the air filter should be changed, how you purchase a replacement filter, or what the filter costs.
We've seen no mention about hand pump lubrication. It costs us $500 for a 20 litre drum of oil for use in our dive compressors. What oil is being used with the Scorkl hand pump, and how often should it be lubricated?
A video is provided to show how to use the Scorkl hand pump.
They recommend not to pump for more than 5 minutes at a time. (We doubt many people could.) Then leave the pump to cool for 15 minutes after each 5 minute pumping period. At the start of each cooling period the bleed screw should be opened so heat and moisture can escape. No indication is given as to how many pumping sessions it typically takes to fill the Scorkl to 100 bar.
Recommended fill pressure is 50–100 bar for ease of use and to optimise pump lifespan. What the...! Now consider this in relation to the warning that you shouldn't descend with less than 50 bar, and that you should begin your ascent at 50 bar.
As the Scorkl founder, David Hallamore, says when talking about filling the Scorkl with the hand pump, "You've got to put your back into it a little bit. It takes a while to fill." We suspect only very fit Scorkl users could achieve a 100 bar air fill using the hand pump anyway. We think most will only achieve 50 to 75 bar. They'll find it too difficult and too exhausting to do more.
Filling The Scorkl Using A Scuba Cylinder
The manufacturer often refers to how the Scorkl can be easily and quickly filled from a scuba cylinder. But no dive shop would hire a scuba cylinder to someone without a scuba diving certification. So there goes being able to do lots of dives in an outing for most of the targeted uncertified diver market for a Scorkl.
Filling The Scorkl At A Dive Shop
References are made to filling the Scorkl cylinder at a dive shop. However, most dive shops when presented with a Scorkl for an air fill would want to see the user's scuba diving certification before filling it. The dive shop would also want to see that the Scorkl cylinder complies with Australian Standards and is in test before filling it.
Filling The Scorkl Using A Dive Compressor
The Scorkl founder, David Hallamore, says he is looking into releasing an air compressor for the Scorkl.
We often get asked by scuba divers whether they could use their compressor at home to fill their scuba cylinder. (One wonders who taught them to dive when divers ask questions like this.) That would be a compressor bought for $200 at Bunnings with no air filtration, that's good for about 100 psi (7 bar).
A scuba cylinder needs to be filled from a compressor capable of some 3,500 psi (240 bar), with an excellent moisture removal and air filtration system. A small home scuba compressor setup like this typically costs around $6,000. The Scorkl is a mini-scuba cylinder.
MiniDive have an electric compressor available for $A2,000. A filter change is advised after every full tank filling. Filters are A$45 each. That's an expensive air fill. This is probably the sort of compressor Scorkl are considering.
How Long Will A Scorkl Last Underwater
They claim the Scorkl is good for 68 breaths (when filled to 200 bar), or up to 10 minutes underwater if you're a good, experienced, relaxed diver. (The 20% larger Scorkl Pro for 80 breaths.) They also say a novice that's chewing through air would only be getting two to five minutes out of it. It's not specified at what depth this is. It would have to be very shallow, we suspect not more than 0.5 metre (1.5 feet).
Scorkl give the following table as the total surface breaths available at various fill pressures, assuming 1.5 litres per breath. We've added the litres of air available.
| Fill Pressure (bar) | 50 | 100 | 150 | 200 |
|---|---|---|---|---|
| Scorkl breaths | 17 | 34 | 51 | 68 |
| Scorkl litres of air | 25 | 50 | 75 | 100 |
| Scorkl Pro breaths | 20 | 40 | 60 | 80 |
| Scorkl Pro litres of air | 30 | 60 | 90 | 120 |
Scuba divers don't talk about air use in terms of breaths. That's because the volume of air used by one breath varies greatly with the depth. At 10 metres it's double, at 20 metres triple, and at 30 metres quadruple. At the maximum depth of 6 metres (20 feet) with a Scorkl, each breath uses 1.6 times more air than that of one breath at the surface. So the Scorkl assumption of 1.5 litres per breath becomes 2.4 litres per breath.
A Scorkl 0.5 litre water capacity cylinder pressurised to 200 bar means you have 75 litres of air to breathe before you hit the 50 bar safety limit. But if you can only fill it to 100 bar using the hand pump, you'll only have 25 litres of air to breathe with the 50 bar safety limit. That's not going to last long, so users of the Scorkl are being encouraged to break these safety recommendations by the marketing hype.
Technical scuba divers actually work out from past dives what their air consumption rates are at various phases of their dives and depths. They convert the information to a surface air consumption rate (SAC). They use these values when working out how much air they need to have, including reserves, while planning a dive. The surface air consumption rate (SAC) for a typical relaxed scuba diver is 20 litres per minute (lpm). It will climb to around 30 lpm if they're actively moving about or working, and can be over 60 lpm in a stressful situation.
The recommended maximum decent rate for a diver is 20 metres per minute, so that's 20 seconds down to 6 metres. The recommended maximum ascent rate for a diver is 10 metres per minute, so that's 40 seconds to come up from 6 metres. Thus a dive to 6 metres has a minimum time of 60 seconds (one minute) for the descent and ascent phases.
Relaxed, Experienced Scorkl User
A relaxed, experienced scuba diver with a SAC of 20 lpm at 6 metres deep will use 32 litres of air per minute. Let's assume the good, experienced, relaxed Scorkl diver has the same SAC, even though this is highly unlikely. Using a Scorkl filled to 200 bar you have a total of 100 litres of air available. Thus you get to spend two minutes at 6 metres after taking in the ascent and descent requirements. That's not giving you the recommended air reserve of 50 bar used by scuba divers as a safety buffer.
But a Scorkl user won't be as relaxed as a typical scuba diver, as they won't have a BCD to help them maintain neutral buoyancy. Thus a dive to 6 metres, spending two minutes at 6 metres, for a total dive time of three minutes, would see the typical Scorkl user run out of air and arriving back at the surface with an empty Scorkl. This is not recommended as it can damage the device. It can also kill the user.
Novice Snorkel User
Now lets look at a novice Scorkl diver who they say will be chewing through air would only be getting two to five minutes out of it. This implies a SAC of at best 40 to 80 litres per minute. If we calculate based on a SAC for this Scorkl diver of 50 litres per minute, this implies that at 6 metres deep the novice Scorkl diver will use 80 litres of air a minute.
But using the Scorkl hand pump, the recommended fill pressure is 50–100 bar for ease of use and to optimise pump lifespan. Assume you've worked hard and filled the Scorkl to 100 bar. You now have 50 litres of air available. That's not even enough for the experienced Scorkl diver to safely do a dive and spend one minute at 6 metres! The newbie Scorkl user is going nowhere. They're probably going to empty it on the surface while doing their safety check. They're not going to get to 6 metres deep and back!
If you properly check the Scorkl as recommended before use by purging it and breathing from it, we doubt a Scorkl filled with the hand pump will have enough air for you to get to 6 metres, let alone stay there and return safely.
Boat Owner Scorkl User
They make mention of how the Scorkl is great for boat owners. Examples given are:
- Unsnagging An Anchor — You're not unsnagging anything if it's more than 6 metres deep. You'd need to freedive down and only use the Scorkl on the bottom, where it won't last long. Then you'll probably be ascending when you've run out of air. You're not a trained freediver. You're not a trained scuba diver. Good luck with that!
- Clearing A Propeller — Let's say the propeller is 1 metre deep. You'll be working, so lets use a SAC rate of 40 litres per minute, which we think is generous. That calculates as using 44 litres of air per minute. If you've used the hand pump to fill the Scorkl to 100 bar, you have only 50 litres of air. With the pre-dive safety check done, you have less than a minute to clear that propeller, and then you're pumping up the Scorkl again with the hand pump. Good luck with that!
- Cleaning The Bottom Of The Boat — Let's say you're now 2 metres deep and working hard again. Using a generous SAC of 40 again, that's now 48 litres per minute and you only have a total of 50 litres available. So you have less than a minute to clean the boat, and then you're pumping up the Scorkl again. Given how many minutes it's going to take to clean the boat's hull, you really are a glutton for physical punishment!
Spearfishing Scorkl User
They make mention of using the Scorkl for spearfishing. Well for a start, spearfishing on scuba is illegal in most Australian states and the Scorkl is scuba gear. In the spearfishing world, spearfishing on scuba is considered bad form, as it's unfair to the prey, and also the thrill of the hunt is gone.
If you do use a Scorkl for spearfishing, remember that you have a maximum depth of 6 metres. Assuming you breath hold down to 6 metres, and your Scorkl has been filled to 100 bar with the hand pump, you have 50 litres of air maximum, but less after you're done the safety checks. Using a SAC of 30, which is very generous, you have one minute at the bottom, before you're ascending without any air. Less, if you follow the safety instructions. Then it's back to shore to pump up the Scorkl again.
More About Scorkl Dangers
If you ignore the glossy marketing hype targeting unknowing people without scuba diving certifications who thus don't know what vital questions to ask, and take into account the recommended limits of the Scorkl, it's a dud device. People typically won't be able to achieve the results promoted, and even if they have read and understood the user manual, they are at great risk of killing themselves.
The marketing slogan for the Scorkl is, "Breathe underwater with TOTAL freedom." We think it should be, "Kill yourself underwater with total ease!"
For another take on the Scorkl, please view the video Scorkl: BUSTED! on YouTube.
You can also listen to an interview with Scorkl founder David Hallamore at NSP:114 David Hallamore SCORKL — Noob Spearo Podcast.
Questions People Ask Us About The Scorkl
- Is Scorkl safe?
- No, they are deadly dangerous! This is a suicide device, wrapped up as a toy. Even fully trained and certified scuba divers would have trouble staying alive just using a Scorkl.
- How long does a Scorkl tank last underwater?
- Not long enough! The marketing hype says the Scorkl is good for 68 breaths (when filled to 200 bar), or up to 10 minutes underwater if you're a good, experienced, relaxed diver. (The 20% larger Scorkl Pro for 80 breaths.) Scorkl also say a novice that's chewing through air would only be getting two to five minutes out of it. It's not specified at what depth this is. If using the hand pump it's recommend to only fill the Scorkl to 100 bar (if you can). That halves those figures to 5 minutes and 1 minute, if you're totally ignoring all of the safety recommendations. We suspect those figures are based on being at a very shallow depth.
- What is the maximum depth for the Scorkl?
- Scorkl say it's "certified" to 6 metres. But the Scorkl is not CE EN2050:2014 certified. We have no idea as to what certification standard Scorkl are claiming to comply with.
- What pressure can the Scorkl be filled to?
- 200 bar using a scuba cylinder or compressor. 50 to 100 bar using the Scorkl hand pump. No dive shop would hire a scuba cylinder to a non-certified diver. No dive shop would fill the Scorkl of a non-certified diver. A dive shop will only fill a scuba cylinder which complies with Australian Standards and is in test. So, as a non-certified scuba diver you're not going to get a 200 bar air fill. It's going to take a long time and a lot of effort to fill a Scorkl to 100 bar using the hand pump.
MiniDive Dangers
Much of what we've covered above for the Scorkl also applies to the MiniDive. The marketing hype used for the MiniDive is more conservative. They say it has a max depth of 3 metres for non-divers, but that it works at up to 50 metres. The MiniDive uses a separate second stage regulator on a low pressure hose. The MiniDive has a harness so that you're less likely to loose it. These are thought out changes, but we still consider it deadly dangerous and a suicide device.
Smaco Dangers
Much of what we've covered above for the Scorkl also applies to the Smaco. The marketing hype used for the Smaco is similar to that of the Scorkl. The Smaco uses a separate second stage regulator on a low pressure hose. The Smaco has a SPG to allow you to monitor the air pressure in the cylinder, but you have to remove it from your month to see it. These are thought out changes, but we still consider it deadly dangerous and a suicide device especially in the hands of non-certified divers.
If you're a certified scuba diver looking for an emergency or redundant air source solution, please see Buying an Emergency Air Source, or shop for Emergency Air Systems.
Warning
Using devices which allow you to beathe at depth underwater without learning to scuba dive is deadly dangerous. Without the proper training you just don't know how many ways there are tp cause yourself serious injury, or kill yourself. You don't know how to do it safely. If you want to spend more time underwater you need to learn to freedive or scuba dive. There are no cheap shortcuts.
See also, Full Face Snorkel Mask Dangers.
