thanks dieseldave and all other who contributed it all makes sense now to a non ADR person, well to me anyway 
while on the subject i know i asked the question in another topic but not sure if you saw it DD, but it was to do with school chemisty and i wondered how is caesium transported as we were told it’s highly volitile and will even react with moisture in the air and can burn through glass 
, that if it does even get transported.
cheers all.
dieseldave:
nick2008:
put it short if its on fire or leakin RUNHi Nick, I think your course of action in the event of fire is fair enough, cos you wouldn’t really want to hang about nearby.
However, if it’s only a leak, then switching the engine off and removing any ignition sources is the thing to do.
Most folks get themselves all excited about UN Class 3, but many don’t realise how it works.
Kerosene has a flashpoint of approx 35 degrees C, so if it’s leaking or spilled and the ambient temperature is anything less than 35 degrees C, then Kerosene vapour simply cannot be ignited. If the ambient temperature is >35 degrees C, there must be a sufficient vapour/air mixture (in the range 1% - 6% for Kerosene) and a sufficiently hot heat source in order for a fire to take place. If the concentration of Kerosene vapour/air is outside of the 1% - 6% flammability limits (ie. either too rich or too weak) then the mixture simply isn’t ignitable.
Many folks get the definitions of ‘flashpoint’ and ‘auto-igniton’ temperatures confused.
Kerosene has an auto-igniton temperature of approx 250 degrees C.The UN has placed Kerosene in Packing Group III of UN Class 3, so that means that the law views Kerosene as being of a low danger.
Check out what brought the Concorde down in Paris.It was leaking cool kerosene from a ruptured fuel tank coming into contact with a damaged electrical cable in the wheel bay.Effectively it’ll go up in just the same way as petrol given exactly the same source of ignition in the right/(wrong) circumstances.
Cruise Control:
thanks dieseldave and all other who contributed it all makes sense now to a non ADR person, well to me anyway
Hi Cruise Control, I’m glad to be able to help. 
Cruise Control:
while on the subject i know i asked the question in another topic but not sure if you saw it DD, but it was to do with school chemisty and i wondered how is caesium transported as we were told it’s highly volitile and will even react with moisture in the air and can burn through glass
Sorry mate, I didn’t see your question in another topic. 
“Volatile” isn’t a word associated with Caesium, because (in ADR) ‘volatile’ means that something evaporates easily, so we tend to use that word when describing the dangers of flammable liquids in UN Class 3. I’d suggest that a better word for describing Caesium is the word “reactive.” (Caesium is in PGI of UN Class 4.3, so it’s said to be ‘highly reactive.’)
For moving caesium around by road, the following are legal requirements:
The ‘stuff’ is:
UN 1407 CAESIUM, 4.3, PGI
The required label/placard looks like this:
Due to its extreme reactivity towards oxygen, water and acids, contact between Caesium and water (including water vapour) and air must be avoided under all circumstances. Caesium (pure form) is described as a gold-coloured metal, which can be a liquid or a solid.
The requirements/specifications for packages containing Caesium are very detailed indeed, and include a requirement for hermetic seals. It is legal to transport Caesium by road in packages or by road tanker, but carrying Caesium loose in a tipper would be illegal. Caesium isn’t allowed to be carried by the use of Limited Quantity exemptions or by Excepted Quantity exemptions, but a non ADR-trained driver is allowed to carry up to and including 20kg/lit of it without an ADR licence. 
(Strange, but true. 
)
dieseldave:
Cruise Control:
thanks dieseldave and all other who contributed it all makes sense now to a non ADR person, well to me anywayHi Cruise Control, I’m glad to be able to help.
Cruise Control:
while on the subject i know i asked the question in another topic but not sure if you saw it DD, but it was to do with school chemisty and i wondered how is caesium transported as we were told it’s highly volitile and will even react with moisture in the air and can burn through glassSorry mate, I didn’t see your question in another topic.
“Volatile” isn’t a word associated with Caesium, because (in ADR) ‘volatile’ means that something evaporates easily, so we tend to use that word when describing the dangers of flammable liquids in UN Class 3. I’d suggest that a better word for describing Caesium is the word “reactive.” (Caesium is in PGI of UN Class 4.3, so it’s said to be ‘highly reactive.’)
For moving caesium around by road, the following are legal requirements:
The ‘stuff’ is:
UN 1407 CAESIUM, 4.3, PGIThe required label/placard looks like this:
Due to its extreme reactivity towards oxygen, water and acids, contact between Caesium and water (including water vapour) and air must be avoided under all circumstances. Caesium (pure form) is described as a gold-coloured metal, which can be a liquid or a solid.
The requirements/specifications for packages containing Caesium are very detailed indeed, and include a requirement for hermetic seals. It is legal to transport Caesium by road in packages or by road tanker, but carrying Caesium loose in a tipper would be illegal. Caesium isn’t allowed to be carried by the use of Limited Quantity exemptions or by Excepted Quantity exemptions, but a non ADR-trained driver is allowed to carry up to and including 20kg/lit of it without an ADR licence.
It’s easy to confuse the difference between Caesium and Caesium 137 though.
Carryfast:
Check out what brought the Concorde down in Paris.It was leaking cool kerosene from a ruptured fuel tank coming into contact with a damaged electrical cable in the wheel bay.Effectively it’ll go up in just the same way as petrol given exactly the same source of ignition in the right/(wrong) circumstances.
Hi Carryfast, whilst that’s perfectly true, most folks miss the point that Kerosene IS far less dangerous than Petrol, because it’s far more difficult to have a correct vapour/air mixture in the first place.
Carryfast:
Is it the same stuff that’s also a by product of nuclear reactors?.
Sorry Carryfast, I’ve no idea.
Carryfast:
So it’s also radioactive as well?.
Not normally mate, that’s why I used the words “pure form” in my reply.
The UN (and therefore ADR) classifies Caesium as a substance that’s dangerous when wet. (UN Class 4.3)
Carryfast:
Best to carry it in a cement mixer in that case.
Sorry mate, that would count as ‘in bulk’ and is therefore illegal.
Carryfast:
Check out how they put the fire out at Chernobyl luckily even the Russians knew that they could’nt use water on it.
Sorry mate, I’m neither a chemist, nor a nuclear engineer, nor a firefighter. I claim no competence whatsoever in those subjects.
Cruise Control:
… not knowing anything about ADR wondered what do these numbers actually meanin laymans terms please
Hi Cruise Control, I’ve just remembered that there’s a topic on tanker marking that I started the other week…
dieseldave:
Carryfast:
Check out what brought the Concorde down in Paris.It was leaking cool kerosene from a ruptured fuel tank coming into contact with a damaged electrical cable in the wheel bay.Effectively it’ll go up in just the same way as petrol given exactly the same source of ignition in the right/(wrong) circumstances.Hi Carryfast, whilst that’s perfectly true, most folks miss the point that Kerosene IS far less dangerous than Petrol, because it’s far more difficult to have a correct vapour/air mixture in the first place.
That’s true in a lot of cases Dave but people seem to concentrate on the volatility of the liquid and the ignition of the gases as being more important than the actual basis of fire itself being the oxidisation of all the fuel.A fire involving a tank full of a flammable liquid will be worse than one that’s just full of that same type of stuff in it’s gaseous state(vapour) for example as there’s much more of it.One will be more of a relatively cool but very dynamic blast the other will be a much hotter burning fire with a possible blast to go with it as the vapours also ignite.Then comes the real nasties of solid stuff like Amonium Nitrate check out the Texas City explosion when the ship Grandcamp blew up.
dieseldave:
Carryfast:
Is it the same stuff that’s also a by product of nuclear reactors?.Sorry Carryfast, I’ve no idea.
Carryfast:
So it’s also radioactive as well?.Not normally mate, that’s why I used the words “pure form” in my reply.
The UN (and therefore ADR) classifies Caesium as a substance that’s dangerous when wet. (UN Class 4.3)Carryfast:
Best to carry it in a cement mixer in that case.Sorry mate, that would count as ‘in bulk’ and is therefore illegal.
Carryfast:
Check out how they put the fire out at Chernobyl luckily even the Russians knew that they could’nt use water on it.Sorry mate, I’m neither a chemist, nor a nuclear engineer, nor a firefighter. I claim no competence whatsoever in those subjects.
Thanks Dave I’ve sorted out the difference now.The radioactive one which I was thinking of is Caesium 137 not the one which is meant here.Those 3 numbers make a big difference.Although I was only having a laugh being encased in concrete might have been a good idea for the one I meant but not in the case of the other one.Hope no one makes the same mistake I did anyway and I reckon that I’m right to not want to get involved with nasties.That idea just run sounds best to me.
why cant they just write in laymans terms on the orange marker boards
for example
“carrying petrol,if its goes up,run like ****” 
Carryfast:
dieseldave:
Carryfast:
Check out what brought the Concorde down in Paris.It was leaking cool kerosene from a ruptured fuel tank coming into contact with a damaged electrical cable in the wheel bay.Effectively it’ll go up in just the same way as petrol given exactly the same source of ignition in the right/(wrong) circumstances.Hi Carryfast, whilst that’s perfectly true, most folks miss the point that Kerosene IS far less dangerous than Petrol, because it’s far more difficult to have a correct vapour/air mixture in the first place.
That’s true in a lot of cases Dave but people seem to concentrate on the volatility of the liquid and the ignition of the gases as being more important than the actual basis of fire itself being the oxidisation of all the fuel.A fire involving a tank full of a flammable liquid will be worse than one that’s just full of that same type of stuff in it’s gaseous state(vapour) for example as there’s much more of it.One will be more of a relatively cool but very dynamic blast the other will be a much hotter burning fire with a possible blast to go with it as the vapours also ignite.Then comes the real nasties of solid stuff like Amonium Nitrate check out the Texas City explosion when the ship Grandcamp blew up.
Hi Carryfast, That’s true again mate, and I’ve checked the Texas City explosion that you mentioned.
In true TNUK fashion, this post started with a simple question that specifically asked for "laymens terms’ about the meaning of a tanker sign and just look what it’s led to…
No matter how much this topic is pulled and pushed, which is quite enjoyable, it’s heading way off the OP’s topic now.
Meanwhile, back at the ranch, the UN (and therefore ADR, IMDG, IATA, RID and ADN) puts most ‘chemical’ type substances into three levels of danger called ‘packing groups’ (PGs,) which are always expressed as Roman numerals on paperwork.
Eg. PGI, PGII or PGIII.
PGI = high danger, PGII = medium danger and PGIII = low danger.
Sticking with UN Class 3 (as in the OP) the three levels of danger (the PGs) are based on how flammable a product is in terms of its flashpoint temperature (FP) and initial boiling point (IBP) temperature.
Class 3
PGI is allocated when a substance has an IBP of <35 degrees C. (In the case of PGI, the flashpoint is irrelevant.)
PGII is allocated when a substance has an FP <23 degrees C AND an IBP >35 degrees C.
PGIII is allocated when a substance has an FP > 23 degrees C in the range <60 degrees C AND an IBP >35 degrees C.
Another function of the PGs is to tell consignors which quality of receptacles/packages can be safely used to transport a particular substance, or the technical features and equipment requirements for a tanker to carry the ‘stuff’ safely. The UN requirements for PGI are therefore more robust and demanding than the requirements for PGIII.
buck rogers:
why cant they just write in laymans terms on the orange marker boards
for example
“carrying petrol,if its goes up,run like ****”
If they did that, how much use would that be in trying to ensure the safety of firefighters called to an incident?
dieseldave:
buck rogers:
why cant they just write in laymans terms on the orange marker boards
for example
“carrying petrol,if its goes up,run like ****”If they did that, how much use would that be in trying to ensure the safety of firefighters called to an incident?
But then again Dave why bother with all the numbers and codes if maybe in the real world it might be better to just identify the actual stuff being carried so the first person/s at the scene who could be any idiot like me could just phone in with exactly what it is and then they know what they are dealing with right from the beginning anyway and the fire brigade should know what to use without being told by the numbered codes anyway too?.As for those flash points and ignition points whoever happens to be in the vicinity wether it’s the driver or the public need to know that it’s not a case of the whole load needing to be at those temperatures before the whole load could go up.A large leak from a ruptured tank coming into contact with something like an electrical short in a broken cable (like that concorde example) can/ will ignite every part of the load that is in contact with the oxygen in the air by chain reaction from the first small part that ignited regardless of wether the rest of the load is below ignition or flashpoint temp?.
Carryfast:
dieseldave:
buck rogers:
why cant they just write in laymans terms on the orange marker boards
for example
“carrying petrol,if its goes up,run like ****”If they did that, how much use would that be in trying to ensure the safety of firefighters called to an incident?
But then again Dave why bother with all the numbers and codes if maybe in the real world it might be better to just identify the actual stuff being carried so the first person/s at the scene who could be any idiot like me could just phone in with exactly what it is and then they know what they are dealing with right from the beginning anyway and the fire brigade should know what to use without being told by the numbered codes anyway too?.As for those flash points and ignition points whoever happens to be in the vicinity wether it’s the driver or the public need to know that it’s not a case of the whole load needing to be at those temperatures before the whole load could go up.A large leak from a ruptured tank coming into contact with something like an electrical short in a broken cable (like that concorde example) can/ will ignite every part of the load that is in contact with the oxygen in the air by chain reaction from the first small part that ignited regardless of wether the rest of the load is below ignition or flashpoint temp?.
All those numbers and codes are there to protect you and me, it is ok relying on Joe Public esquire to ring 999 in a panic. the tanker is leaking in front of me, ok sir, can you tell me what it is carrying? Yes Acid!! quickly quickly. Do you know what kind of acid it is?
1873 PERCHLORIC ACID 5.1
2031 NITRIC ACID 8
As you can see from the blue numbers, Perchloric Acid has a totally different hazard to Nitric Acid
1064 METHYL MERCAPTAN - 2
1247 METHYL METHACRYLATE - 3
2263 DI METHYL CYCLOHEXANES - 3
2264 N,N-DIMETHYLCYCLOHEXYLAMINE - 8
2265 N,N-DIMETHYLFORMAMIDE - 3
How about all these Methyl’s?
You have got gas, flammable liquid and corrosive with very similar names.
Should we not carry on with a tried and tested system that the emergency services, tanker drivers and shipping companies throughout the world can easily understand in any language?
There are over 3500 UN numbers in use, it is easy to read a four digit code which gives immediate information of the hazard class and therefore the dangers, immediate or delayed.
The UN number immediately identifies the product, a trade name may not, have you heard of Perklone, or Genklene?
more readily identifiable as Tetrachloroethylene, UN 1897, Class 6
How about the stuff they use in workshops for degreasing parts, most will not know it contains multiple carcinogenic chemicals, including benzene, perchloroethylene, trichloroethylene, methylene chloride, chlorinated benzenes, and polycyclic aromatic hydrocarbons.
buck rogers wrote:
why cant they just write in laymans terms
Because that ROG bloke would then start posting about ADR
ROG:
buck rogers wrote:
why cant they just write in laymans termsBecause that ROG bloke would then start posting about ADR
Noooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo!!! 
ROG:
buck rogers wrote:
why cant they just write in laymans termsBecause that ROG bloke would then start posting about ADR
Then there would be much wailing and gnashing of teeth in Leicester.
Antidote for
Demented
ROGS
Carryfast:
But then again Dave why bother with all the numbers and codes if maybe in the real world it might be better to just identify the actual stuff being carried so the first person/s at the scene who could be any idiot like me could just phone in with exactly what it is and then they know what they are dealing with right from the beginning anyway
Hi Carryfast, That because foreign types insist on speaking strange languages.
Dangerous goods are shipped worldwide, so there needs to be a system that gets past the problems caused by all those different languages.
The UN has decided that there is a worldwide four-digit numbering system, which nicely avoids languages and fancy-sounding chemical names as mentioned by Wheel Nut.
Here’s the way it works… (Remember the order that I wrote UN 1223 KEROSENE, 3, PGIII)
Let’s imagine a tank container full of Kerosene was loaded in Russia and arrived at the docks… a driver picks up the tank container, then studies the paperwork to discover: â„– OOH 1223 КЕРОϹИÐ, 3, ГУIII
The driver doesn’t actually need to know what the stuff is, but DOES need to know about the “3” and the “III,” so he understands that it’s a flammable liquid that’s not awfully dangerous. That’s why the order that the info is written on the paperwork is so important that it’s a legal requirement. The letters “КЕРОϹИД are very similar to the English “KEROSIN” so if somebody had a slight grasp of the Cyrillic alphabet, they could guess the word.
Now for a proper one:
КИCЛОТРCЕРÐÐЯ. For all we know at this point, it could mean “bacon butty.”
Written correctly:
â„– OOH 1830 КИCЛОТРCЕРÐÐЯ, 8, ГУII
Again, we don’t really need to know what it is, but we can tell it’s a corrosive from the “8” and that it’s medium nasty from the “II”
Transliterating that into our alphabet gives: KISLOTA SERNAYA, so there’s still no clue as to what it is.
A look in any modal Regs (ADR, IMDG, RID, IATA or ADN) written in English tells us that it’s UN 1830 SULPHURIC ACID, 8, PGII
Here’s some 'orrible stuff written in German, can you guess what ‘stuff’ it is?
UN 1830 SCHWEFELSÄURE, 8, VGII
That proves that foreign languages and/or big long unreadable fancy chemical names are completely irrelevant.
Carryfast:
and the fire brigade should know what to use without being told by the numbered codes anyway too?
They do if they first know the four-digit number for what ‘stuff’ they’re up against.
Imagine trying to phone 999 and say this chemical name after a couple of beers:
DICHLORODIFLUOROMETHANE AND DIFLUOROETHANE AZEOTROPIC MIXTURE
I’d find it easier to say that it’s UN 2602, but that’s just me.
Carryfast:
As for those flash points and ignition points whoever happens to be in the vicinity wether it’s the driver or the public need to know that it’s not a case of the whole load needing to be at those temperatures before the whole load could go up.A large leak from a ruptured tank coming into contact with something like an electrical short in a broken cable (like that concorde example) can/ will ignite every part of the load that is in contact with the oxygen in the air by chain reaction from the first small part that ignited regardless of wether the rest of the load is below ignition or flashpoint temp?.
That’s quite true mate, but it’s the sort of thing that you’d need to discuss with a trained and qualified firefighter. My qualifications and remit are as an ADR instructor and ADR Regs consultant (DGSA,) apart from those, I’m an (almost) ex-LGV driver with no in-depth fire training, so I can only tell anybody what ADR and UK Regs say about subjects raised as questions by our forum members. To answer your question, an ADR vehicle driver is trained on an ADR course to know the hazards arising from the carriage of dangerous goods and what to do in an emergency as per the syllabus set by the DfT. WADR mate, if you have a concern about that, I’d suggest that you take it up with the fire-brigade or the DfT, because I’m not qualified on fire-theory or to comment on what should or shouldn’t be written in the law, cos I’m only a foot soldier in the grand scheme of things.
Wheel Nut:
Carryfast:
dieseldave:
buck rogers:
why cant they just write in laymans terms on the orange marker boards
for example
“carrying petrol,if its goes up,run like ****”If they did that, how much use would that be in trying to ensure the safety of firefighters called to an incident?
But then again Dave why bother with all the numbers and codes if maybe in the real world it might be better to just identify the actual stuff being carried so the first person/s at the scene who could be any idiot like me could just phone in with exactly what it is and then they know what they are dealing with right from the beginning anyway and the fire brigade should know what to use without being told by the numbered codes anyway too?.As for those flash points and ignition points whoever happens to be in the vicinity wether it’s the driver or the public need to know that it’s not a case of the whole load needing to be at those temperatures before the whole load could go up.A large leak from a ruptured tank coming into contact with something like an electrical short in a broken cable (like that concorde example) can/ will ignite every part of the load that is in contact with the oxygen in the air by chain reaction from the first small part that ignited regardless of wether the rest of the load is below ignition or flashpoint temp?.
All those numbers and codes are there to protect you and me, it is ok relying on Joe Public esquire to ring 999 in a panic. the tanker is leaking in front of me, ok sir, can you tell me what it is carrying? Yes Acid!! quickly quickly. Do you know what kind of acid it is?
1873 PERCHLORIC ACID 5.1
2031 NITRIC ACID 8
As you can see from the blue numbers, Perchloric Acid has a totally different hazard to Nitric Acid
1064 METHYL MERCAPTAN - 2
1247 METHYL METHACRYLATE - 3
2263 DI METHYL CYCLOHEXANES - 3
2264 N,N-DIMETHYLCYCLOHEXYLAMINE - 8
2265 N,N-DIMETHYLFORMAMIDE - 3
How about all these Methyl’s?
You have got gas, flammable liquid and corrosive with very similar names.
Should we not carry on with a tried and tested system that the emergency services, tanker drivers and shipping companies throughout the world can easily understand in any language?
There are over 3500 UN numbers in use, it is easy to read a four digit code which gives immediate information of the hazard class and therefore the dangers, immediate or delayed.
The UN number immediately identifies the product, a trade name may not, have you heard of Perklone, or Genklene?
more readily identifiable as Tetrachloroethylene, UN 1897, Class 6
How about the stuff they use in workshops for degreasing parts, most will not know it contains multiple carcinogenic chemicals, including benzene, perchloroethylene, trichloroethylene, methylene chloride, chlorinated benzenes, and polycyclic aromatic hydrocarbons.
Yes it’s carrying petrol.How do you know that?.Because it’s written on the sides/back/front of the truck in great big titanium letters.How about coming to a compromise of having all those codes and letters and the full title description of what the stuff actually is too for the simple ones like that on domestic journeys starting in one UK place and finishing in another or maybe even the simple idea of changing description languages at ports of entry for some too then we’d have the best of all worlds?.But as it is it’s often going to take sometime from when Joe Public pulls up behind the tanker that’s just been wrecked and when the the firebrigade get to check all those codes by looking at them if they’re still there when they get there and then have to decide on the right kit for the job?.But yes it’s very easy to see the sense in using numbers to represent the description,hazard type,and the type in those complicated cases?.That’s why tankers are some of the best paying jobs out there but they earn every penny and a lot more?.But those fire fighters often earn a lot less.
Carryfast:
Yes it’s carrying petrol.How do you know that?.Because it’s written on the sides/back/front of the truck in great big titanium letters.How about coming to a compromise of having all those codes and letters and the full title description of what the stuff actually is too for the simple ones like that on domestic journeys starting in one UK place and finishing in another or maybe even the simple idea of changing description languages at ports of entry for some too then we’d have the best of all worlds?.
Hi Carryfast, That might work if you could persuade the tanker firms to adopt the idea. Failing that, you could ask the DfT to take a look at it.
I’m guessing that you’d meet some resistance from the tanker firms who probably feel that they have enough compliance costs already.
Carryfast:
But as it is it’s often going to take sometime from when Joe Public pulls up behind the tanker that’s just been wrecked and when the the firebrigade get to check all those codes by looking at them if they’re still there when they get there and then have to decide on the right kit for the job?.
Your scenarios seem to have the driver incapacitated and the load documentation lost each time you make a suggestion. IMHO, Joe Public is perfectly capable of realising that tankers carry nasty ‘stuff’ and to stay away from the tidal wave of leaking ‘stuff.’ The everyday reality is that tanker accidents are quite rare and that, due to legally required design characteristics, leakages are also rare. You may not know this, but most tankers have a footvalve (imagine a bath-plug) inside the tank, as well as the valves and caps that you can see. There is a system, and it’s pretty good. Trust me!!
Carryfast:
But yes it’s very easy to see the sense in using numbers to represent the description,hazard type,and the type in those complicated cases?..
That’s a good point mate, but I think it raises another question…
Who gets to define “complicated?” (By whose measure is something to be called “complicated??”)
To a person who doesn’t know much about any given subject, almost all of that subject would probably seem “complicated.”
If it’s “complicated” now, why add yet more requirements?? (Which might complicate things even more. )
