Hi everyone! Tried searching the forum before posting this, but couldn't get proper answers. Is it ok to wear a watch while jumping from a height of 10 feet (3 meters)? Will the impact be too much for the watch to handle? The watch has a WR of 300m if that helps.
Jumping in water with a watch?
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crazyfingers
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I am pretty sure if it is a well made watch then there is absolutely no risk. I can't be bothered to dig out the equations needed to prove anything but I would be ok diving from 3m if I had to.
I am not sure it is fair to say straight out that if it doesn't harm you then it won't harm the watch, because depending on how you land, 3m is more than enough to cause a bit of pain. And the human body is capable of coping with forces that watches can't. Sudden shocks can damage a watch without harming the person wearing it. I also don't think it is correct to say that fluid dynamics and the path of least resistance means that any pressure caused by movement is negligible. If that were the case you would never feel water pressure because it would flow around you. You would never feel the effect of waves underwater when diving, which you do. You would never feel the force of wind because it would flow around you. The whole field of aerodynamics would be incorrect and redundant... It has been a while since I studied it at university so maybe I have remembered it wrong or am using the wrong terminology!
You will be fine though [emoji4]
Current collection: Grand Seiko Hi Beat, Seiko 5, Nomos Tangomat, one crappy watch I made myself (it was fun)
I am not sure it is fair to say straight out that if it doesn't harm you then it won't harm the watch, because depending on how you land, 3m is more than enough to cause a bit of pain. And the human body is capable of coping with forces that watches can't. Sudden shocks can damage a watch without harming the person wearing it. I also don't think it is correct to say that fluid dynamics and the path of least resistance means that any pressure caused by movement is negligible. If that were the case you would never feel water pressure because it would flow around you. You would never feel the effect of waves underwater when diving, which you do. You would never feel the force of wind because it would flow around you. The whole field of aerodynamics would be incorrect and redundant... It has been a while since I studied it at university so maybe I have remembered it wrong or am using the wrong terminology!
You will be fine though [emoji4]
Current collection: Grand Seiko Hi Beat, Seiko 5, Nomos Tangomat, one crappy watch I made myself (it was fun)
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As posted above...recently a few gave technical scientific formulas and Blah Blah Blah....water displacement Blah Blah...your body would explode first Blah Blah. If your watch gets hurt you aren't coming up. I used to jump in the water with my wife.....she ALWAYS survived the hit !!! Glug...Glug....
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This has been dicussed at length before and the misinterpretation of fluid dynamics has been thoroughly debunked by members that are very knowledgeable of physics (not me!). The gist of it is that you would have to be moving very, very fast for the speed of water to have a substantial effect beyond the depth rating. At that speed, the bigger problem is not your watch. Like many other members here I've jumped off dive boats with a couple different 300m watches. That's what they are made for.
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I think you may will be fine.
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Calculating the exact forces against the watch would be very very difficult. Calculating the maximum possible pressure spike the watch would see is very easy. Assuming you don't punch the water when you go in, you'll hit at 7.67 m/s. This will create a maximum velocity pressure from the water of about. 4.3 psi. While that's enough to hurt you a little, it's irrelevant to the watch. You will get a hammer effect as you and the watch are suddenly decelerated from 7.67 m/s back to zero, but it will be way below the 5000 or so g's the watch is designed to handle.
Think about it- if you hit the water hard enough to push water past the seals on a 200m watch, you would have a velocity pressure on the order of 300 psi. Imagine what that would do to the human body.
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Think about it- if you hit the water hard enough to push water past the seals on a 200m watch, you would have a velocity pressure on the order of 300 psi. Imagine what that would do to the human body.
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Depending on the integrity of your seals and O-rings, that type of impact could possibly force water into the case. Also, if you hit the water the wrong way, it might loosen the hands...among other parts.
I might do it with a $100-$200 watch, but not with anything expensive.
If you feel the need to jump in the water from 10 feet I would first suggest handing your watch over to a good friend while on dry land.
I might do it with a $100-$200 watch, but not with anything expensive.
If you feel the need to jump in the water from 10 feet I would first suggest handing your watch over to a good friend while on dry land.
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Let's do the math. A jump from a height of 10 feet, involves a bodily acceleration of 44mph, albeit in a marginally short period. An impact at 44mph creates roughly 3000 Gs. So, first of all, you need to check if your watch meets the International Standard ISO 1413, which is measured using a pendulum impact-testing machine. Check the manual from Panerai. But shock resistance of the movement is only the first part of the equation. Now you have to think about WR in absolute terms, not what's listed on the dial. On the dial, sure, it says that it can withstand 300m of pressure, BUT does it specify which wrist? Depending on whether it's on the right or left wrist, and depending on the speed of the wind at the time of the jump, and depending further on the size of your wrist versus your body mass index, the water resistance of a watch can depart drastically from what's printed on the dial. Think of the 300m WR on the dial simply as a general guide. To reveal the TRUE water resistance of the watch you need to divide the nominal water resistance number (printed on the dial) by the wind speed at the time of the jump, then multiply that number by your body mass index minus your wrist size measured in inches. Then, either add 50 (for right wrist) or subtract 50 (for left wrist) and that will give you the true water resistance of the watch. For a 10m dive, you're going to need at least 120m TRUE WR. The number printed on the dial means nothing. I'd also advise you to have both the watch and your wrist insured prior to taking the dive. Sometimes if you insure the watch but do not also insure your wrist, then the underwriter for the watch won't pay out for the watch if it's revealed that your wrist was also injured (but uninsured) during the dive. Additionally, given the substantial height of your dive, a word of caution: you should have emergency medical personnel on site before you undertake the dive. You never know what can happen, and you want to have trained medics on hand if something should go wrong.
Let's breakdown the formula again:
Stated WR divided by wind speed at time of jump, multiplied by your body mass index minus your wrist size, then add 50 (right wrist) or subtract 50 (left wrist).
![Image]()
Let's breakdown the formula again:
Stated WR divided by wind speed at time of jump, multiplied by your body mass index minus your wrist size, then add 50 (right wrist) or subtract 50 (left wrist).
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1) As already noted, the additional pressure on the seal from impacting the water is negligible. Water does not go into difficult places when there are easy places to go instead. If the seals are that bad, then simply submerging the watch would also let water in and the jump is irrelevant.
2) The abrupt velocity changes experienced by a watch on the wrist in daily wear are much greater than that experienced by a watch hitting the water. If the hands do not loosen from daily wear, they will not loosen from jumping into water.*
* Unless you jump from such a great height or in such an absurd spread-eagle belly flop that you stop dead at the surface of the water**, at which point (again, as noted earlier) the watch is the least of your problems, because it will take much less damage than its wearer will.
** Frozen water*** will also achieve this.
*** Also known colloquially as "ice."
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How good is your entry?
![Image]()
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Might want to check your math. I think you forgot to include time of day, position of the moon, and emotional state of the jumperLet's do the math. A jump from a height of 10 feet, involves a bodily acceleration of 44mph, albeit in a marginally short period. An impact at 44mph creates roughly 3000 Gs. So, first of all, you need to check if your watch meets the International Standard ISO 1413, which is measured using a pendulum impact-testing machine. Check the manual from Panerai. But shock resistance of the movement is only the first part of the equation. Now you have to think about WR in absolute terms, not what's listed on the dial. On the dial, sure, it says that it can withstand 300m of pressure, BUT does it specify which wrist? Depending on whether it's on the right or left wrist, and depending on the speed of the wind at the time of the jump, and depending further on the size of your wrist versus your body mass index, the water resistance of a watch can depart drastically from what's printed on the dial. Think of the 300m WR on the dial simply as a general guide. To reveal the TRUE water resistance of the watch you need to divide the nominal water resistance number (printed on the dial) by the wind speed at the time of the jump, then multiply that number by your body mass index minus your wrist size measured in inches. Then, either add 50 (for right wrist) or subtract 50 (for left wrist) and that will give you the true water resistance of the watch. For a 10m dive, you're going to need at least 120m TRUE WR. The number printed on the dial means nothing. I'd also advise you to have both the watch and your wrist insured prior to taking the dive. Sometimes if you insure the watch but do not also insure your wrist, then the underwriter for the watch won't pay out for the watch if it's revealed that your wrist was also injured (but uninsured) during the dive. Additionally, given the substantial height of your dive, a word of caution: you should have emergency medical personnel on site before you undertake the dive. You never know what can happen, and you want to have trained medics on hand if something should go wrong.
Let's breakdown the formula again:
Stated WR divided by wind speed at time of jump, multiplied by your body mass index minus your wrist size, then add 50 (right wrist) or subtract 50 (left wrist).
![Image]()
Will- BS in physics, BS & MS in mechanical engineering.
Sent from my iPhone using Tapatalk
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Thanks! I'll look it up.
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Thank you all for your input! Some of the science stuff went over my head but I appreciate the feedback. I'll make sure to double check the crown is secured with the crown guard. I'll try to evaluate the situation while I'm there, if it feels too high, I'll probably hand the watch over to my fiancé.
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One obvious question is whether you're jumping in head first or feet first. If you're landing feet first, then your velocity would have been decreased substantially by the time the watch enters the water.
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Definitely feet first. Maybe head first for something around 1 meter.
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Apparently this is the same effect on the watch as moving your arm about underwater, which we also know as "swimming".
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Everybody knows that if you're wearing a watch the only way to prevent water damage is to hold your arms perfectly still down at your sides.Apparently this is the same effect on the watch as moving your arm about underwater, which we also know as "swimming".
Of course that usually results in the human wearing the watch drowning... but at least the watch was saved.
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Head first or feet first? Man, that's what I've been doing wrong all these years. I've been trying to do both at the same time!
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