M26 valves

In article <1189513575.403890.196040@19g2000hsx.googlegroups. com>,
"jazzie129uk@yahoo.com" <jazzie129uk@googlemail.com> writes
>As I understand it, any tank (and hence first stage) being filled with
>a mix of higher than 22% Oxygen needs to have an M26 valve fitted to
>it, which has a slightly larger fitting than yer average DIN. The
>logic behind it appears to be to prevent a reg not suited for high
>levels of O2 being used with high levels of Oxygen by mistake.
>
Some one will produce an insert to screw into the M26 thread to enable a
yoke clamp to be used the same as with a M25 Valve. Or if they do go
ahead with an obstructer (shape size of valve head etc) method to
prevent a clap valve being used over an insert, then an adapter to
permit a clamp valve to be used.

Can anyone see the problem with this as the objective of the rules
(apart from being ill thought through) it to make partial pressure
filling safer. The blended gas going through the first stage is going to
be less then 40% for normal requirements.

Then again, several private air stations will just ignore the rules.

For example. I know of a large extended family all of whom dive. They
have their own compressor and partial pressure blend. They have an
investment of 30 odd tanks and 12 sets of regs.
--
Mick Whittingham
'and I will make it a felony to drink small beer.'
William Shakespeare, Henry VI part 2.

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee

Mick Whittingham wrote

> Some one will produce an insert to screw into the M26 thread to enable a
> yoke clamp to be used the same as with a M25 Valve. Or if they do go ahead
> with an obstructer (shape size of valve head etc) method to prevent a clap
> valve being used over an insert, then an adapter to permit a clamp valve
> to be used.
>
> Can anyone see the problem with this as the objective of the rules (apart
> from being ill thought through) it to make partial pressure filling safer.
> The blended gas going through the first stage is going to be less then 40%
> for normal requirements.

I certainly see a problem with it. What I don't see is that it's a solution
to anything. As I recall, you guys have to have special markings on your
tanks to use nitrox in them, right? Are you telling me that that your fill
techs can't see the markings, so they need a different valve to guarantee
they only put nitrox in a nitrox tank or are you telling me that your divers
are so numb that they can't see the markings and dive nitrox like it was air
or air like it was nitrox? I think better of your people than you do.

The only thing I can see that this does is make it very hard, more likely
expensive, for someone that sometimes breathes nitrox and sometimes breathes
air. You're likely to need two sets of regulators or, at least, two first
stages, all for no gain at all.

Lee