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Posted By Paul D
I have finally got my head around REACH regulations, with help from posters on here I may add, thank you all.
Now, when I want to know something, I want to know everything, within the REACH glossary a 'substance' is defined as below;
'A chemical element and its compounds in the natural state or obtained by any manufacturing process, including any additive necessary to preserve its stability and any impurity deriving from the process used, but excluding any solvent which may be separated without affecting the stability of the substance or changing its composition'
Can somebody translate this into something I can easily convey to my MD as I don't understand it myself!!
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Posted By Robert K Lewis
It is any material that you encounter in whatever form it exists, even dissolved in a solvent providing that the solvent does not change its character.
Thus cement is a substance whch is an admixture formed from a process that changed the nature of the original state of the materials to form a new material that has specific characteristics. The addition of additives to the cement does not change it from being cement as a substance.
Good circularity as always from policymakers and drafters!!!
Bob
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Posted By Jane Blunt
An interesting question.
As defined in the post above, I would not have classified cement as a substance, because it is a proprietary mixture of several chemical compounds, each of which is in fact a substance as defined by that phrase. The additives are not there to preserve its stability, but to do things like promote setting or improve the mechanical properties of the set product.
Jane
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Posted By garyh
I think that what is being conveyed is that a substance is a single chemical eg Copper (metal) or Copper Sulphate or Copper Nitrate - all single substances. So Methanol, or Benzene etc are all "substances".
You also have "preparations" which are mixtures of many chemicals eg Crude oil, Petrol, Creosote etc have many many substances in them.
This is the sort of terminology used in preparing things like safety data Sheets etc.
Hope this helps.
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Posted By wayne purchase
a substance is the chemical in its raw state, cement is a preparation of substances.
hope this helps?
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Posted By NJS
just to be pedantic because its early, i found many definitions, pick the one that fits:
1. that of which a thing consists; physical matter or material: form and substance.
2. a species of matter of definite chemical composition: a chalky substance.
3. controlled substance.
4. the subject matter of thought, discourse, study, etc.
5. the actual matter of a thing, as opposed to the appearance or shadow; reality.
6. substantial or solid character or quality: claims lacking in substance.
7. consistency; body: soup without much substance.
8. the meaning or gist, as of speech or writing.
9. something that has separate or independent existence.
10. Philosophy. a. something that exists by itself and in which accidents or attributes inhere; that which receives modifications and is not itself a mode; something that is causally active; something that is more than an event.
b. the essential part of a thing; essence.
c. a thing considered as a continuing whole.
11. possessions, means, or wealth: to squander one's substance.
12. Linguistics. the articulatory or acoustic reality or the perceptual manifestation of a word or other construction (distinguished from form).
13. a standard of weights for paper.
(dictionary.com)
however a controlled substance can be more specificaly defined as:
A controlled substance is generally a drug or chemical whose manufacture, possession, and use are regulated by a government. This may include illegal drugs and prescription medications (designated Controlled Drug in the United Kingdom).
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Posted By CFT
Paul
Personally I don't think it is a case of 'one cap fits all' regarding your question and you would do well to spend some time looking at the different types of substance.
REACH considers; 'substances with a defined qualitative and quantitative composition.'
Note then how the plural use of the word changes the way in which one can explain what a substance actually is. For me, and just as one example a substance is 'something in its raw state' or indeed obtained by any manufacturing process; does then the mixture of several substance or raw compound eventually become another type of substance?
Taking cement just as one example (and I do agree with Jane) several parts or substances (note the plural) make up the whole part; would you then refer to cement as a substance? Almost certainly not, but would you be that wrong if you did?
You can actually interpret this in many ways and it does go on a bit to consider, is it an element or a compound (like oxygen or carbon dioxide respectively) both are actually a substance, an element cannot be broken down further by chemical reactions, so it can be termed as a substance it its raw state.
Sorry, it's a bit heavy for the morning;-)
CFT
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Posted By Dave Daniel
Look on the ECHA (REACH) website. You'll find they have published documents which aim to describe at length (and I do mean length!) on the difference between an article and a substance and what a "substance" is. Be prepared to be none the wiser and end up suspecting that even the ECHA don't really know!
I must confess getting the feeling they've bit off more than they can chew as many were telling them before the EC Directive was signed.
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Posted By MickN
The difficulty here is the non scientific versus the scientific points of view. To answer your question, a substance is a single, identifiable, measurable and stable chemical made up of one or more elements.
Table salt: NaCl, Sodium & Chlorine. Substance. If you dissolve it in water it's still a substance only now "in solution", i.e. you could boil off the water and again be left with salt in it's solid state.
As for the stability thing, many chemicals we use today are found naturally only for us to add or remove bits to make them "usable". Asprin is derived from Salicylic Acid and if I remember the story correctly was discovered due to someone digesting tree sap. In the tree sap form it's highly unpalatable but it did relieve some pain and reduce temperatures so the chemists played around with it and produced a version that maintained the helpful properties and could be swallowed without everyone getting sick.
Most chemicals break down over time and so some (like medication) need help to hold it together longer.
Hope this helps
Mick
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Posted By Mitch
Paul,
In relation to what products are you requiring definition in laymans terms?
Mitch
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Posted By Paul D
Mitch,
Not any product really, as I have said in my original post I have finally got REACH sorted in my head with our role, what we should do or not do etc.
It is just something I would just like to clarify.
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Posted By SteveD-M
Paul
There are some short and to the point explanitory documents on REACH on the HSE website.
Substance
A chemical element and its compounds in the natural state or obtained by any manufacturing process, including any additive necessary to preserve its stability and any impurity deriving from the process used, but excluding any solvent which may be separated without affecting the stability of the substance or changing its composition.
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Posted By NJS
I tried but the moderators blocked my answer!
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Posted By IOSH Moderator
NJS
Your response was hidden as the information came directly from 'Dictionary.com' part of an Ask.com service, which in turn is covered by copyright restriction as detailed here:
'Copyright © 2008, Dictionary.com, LLC. All rights reserved' (This short extract fully credited to 'Dictionary.com.'
Mike
IOSH Moderator
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Posted By Jane Blunt
In this instance the dictionary definition is very little help. We already have a legal definition emanating from REACH, the trick is in understanding its scope and meaning.
Jane
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Posted By Robert K Lewis
Cement is derived from the kilning of calcium carbonate and added minerals to produce a compound of required composition. It exits the kiln in clinker form and is crushed with Gypsum additive to ensure its stability and setting rate. For me it is a substance.
Still I am only an ignorant chemical engineer by training and cannot match these policy writers with their byzantine mindsets and labyrinthine modes of expression. I think we will have to go back to the overall intention of REACH and bear in mind what it was hoping to achieve
Bob
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Posted By Jane Blunt
Bob, your response got me to pull out my book!
The calcium carbonate decomposes to give lime, CaO, and carbon dioxide.
Portland cement is a mixture of three basic ingredients: a lime/alumina compound, and two different lime/silica compounds. When mixed with water it hydrates and forms several new complex products. So it is a mixture of several substances, both before and after it is mixed into concrete.
I agree with ou about REACH ;o)
Jane
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Posted By SteveD-M
Paul
I gave you the official definition of a substance straight from Article 3 of REACH. This would be the LEGAL definition.
Substance
A chemical element and its compounds in the natural state or obtained by any manufacturing process, including any additive necessary to preserve its stability and any impurity deriving from the process used, but excluding any solvent which may be separated without affecting the stability of the substance or changing its composition.
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Posted By Ian Futcher
I am sometimes amused by these fora, and sometimes flabbergasted.
Steve D-M: I am saddened by a somewhat superior reply to Paul; He knows the definition, since he quoted it in his original question. The poor guy is flummoxed by it; simply pointing him back to it and repeating it ever louder will not resolve his query.
I am a chemist by education and a trainer by vocation, and a Safety Specialist by employment. I am educated with a high IQ (147 is pretty high I think). Yet even I sometimes have to wrestle with the meanings of sentences and phrases in some legislation.
So, Paul, you're not alone; it's not easy to try and explain something in simple terms to someone else when you are not understanding it yourself.
Some of the examples about cement show how even experienced people will come up with different explanations... Hopefully there will be some more examples and overall you will get the gist.
Ian
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Posted By SteveD-M
Sorry Paul wasn't directed at you.
:(
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Posted By Mitch
Paul,
Rather than getting bogged down in cement I'll elucidate my earlier question. Can you tell us what products/industry you work with/in so that someone may give you a meaning relevant to your MD's experience?
Mitch
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Posted By Paul D
Ive had a good example come to light today, is the sticky bit on the back of adhesive tape classified as a substance?
Ive had the usual mountain of REACH requests this week and one customer wants to know if we have made sure the stickiness has been pre registered.
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Posted By MickN
Paul, Yes is a glue/adhesive and as such it's a chemical substance.
Interestingly (or maybe not) I worked on a construction project where we had to re-order all safety helmet stickers as there were questions regarding the adhesive being used. The fear was that the adhesive would weaken the helmet/plastic structure!
A solution, I'm sure you're relieved to know, was found in the end and none of the helmets fell to bits as a result of dodgy adhesive.
Mick
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Posted By Tabs
If the sticky is being used as part of an adhesive tape, it is an article. If the backing is removed and the sticky left in position it is a substance.
(ref a very qualified person at the Barbour seminar I attended yesterday).
Salt from sea or ground exempt registration, salt synthesized must be registered, both a substance.
Ingot of copper = substance, copper wire = article. (they don't want to keep registering a substance in every form it can take).
Oxygen exempt substance, zinc exempt substance, come up with a new combination of both = new substance because it is a new chemical (ok - I know zinc oxide exists but I mean a new "thing" maybe Zn8O3 if such could exist (valency of Zn not in my recall)).
My (layman) take away yesterday is that a substance is the lowest building block of a compound, in it's "as made" state.
Does that help?
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