One-handed scuba signals - for numbers - do you use?

[BRT]

Thousands are fingers on the opposite arm, hundreds are fingers held up. How would anyone not know this????

 

[D_Fresh]

Too many times I've had people in a black wetsuit and black gloves try to show me their fingers with their hand held in front of their body.

Totally concur. This is why I buy gloves with white palms and fingers. If I dive with somebody who has black palms and fingers, I tell them up front their hand signals won’t be distinguishable.

Yes yes yes, could not agree more. I have the benefit of diving warm water, so I often don't wear gloves, but when I do, I use the cotton mesh kind from the local hardware store. The glove body is white-ish and the palms are either blue or orange. Super cheap, fairly durable really, quick drying, and very visible.

 

[kelemvor]

Military method
We used to flash fuel states to each other when flying in formation in radio silence
Finger(s) vertical is 1 to 5
Finger(s) horizontal is 6 to 9
Clenched fist is zero

For example:
2 fingers held vertically = 2
2 fingers held horizontally = 7

1800 p.s.i. is
1 finger held vertically, which is "1"
3 fingers held horizontally, which is "8"

The clenched fist is obviously dependent on the situation. If you and your team are communicating gas, then the clenched fist obviously means "zero" and not "hold."

If a team mate comes up to you out of the blue and shows you a clenched fist, then it obviously means "hold" and not "zero."

Hah. I didn't know that was "the military method". That's what I recall learning in OW class (naui shop). I once had someone give me a hard time saying that I wasn't doing the signs right and assumed that I'd just remembered the signs wrong. Now I know there's a couple ways to do it and both must be fairly common.

Clearly the hand signals have a significantly reduced value due to the multiple standards. In a world with 246 scuba certification agencies, standards aren't all that standard.

I really like @Prometheanfire's binary method. Maybe something worth committing to memory