PART TWO
REACH touches
BRAZING!
Jack Willingham, Manager Quality & Technical Service at
Johnson Matthey Metal Joining
discusses how EU Reach is touching brazing materials
in this, the second part of his article on the
implications of the EU Reach regulations.
24
THE EUROPEAN UNION’S REACH regulations are continuing to touch the metal joining industry. This article looks at how REACH is affecting brazing materials and explores current and future developments on the classification of brazing fluxes.
So how is REACH touching brazingmaterials? Cadmium and cadmium oxide are classified as carcinogens and posing acute and chronic aquatic toxicity. The classification of these substances resulted in the EU enacting legislation that came into effect on 10th
2011 banning the sale of cadmium containing silver brazing filler metals, which had been used in industry since the mid-1930s, and imposed a maximum impurity limit for cadmium in any type of brazing filler metal of 0.010%. REACH is also an important consideration for suppliers
of brazing fluxes. Some brazing fluxes have already been reclassified in terms of the hazard labelling because of the chemicals that they contain. For example, many brazing fluxes
contain boric acid – a chemical included on the SVHC list which has been classified as being toxic for reproduction. Whilst such a classification may raise understandable concerns over the apparent repro-toxic nature, it is important to understand that this classification resulted from animal studies based on ingestion of the substance. In reality, the chances of any human voluntarily ingesting the substance in volumes that equate to those administered in the animal studies are remote. It should also be noted that boric acid is a substance
December
that has many uses and is present in many products including cosmetics. In addition to boric acid, another substance commonly
used in high temperature brazing fluxes has similarly been classified and included on the SVHC list – disodium tetraborate anhydrous, also known as sodium tetraborate, but more commonly as borax. Sodium tetraborate (borax) has a sister compound that is present in most fluxes used with silver brazing filler metals, potassium tetraborate, which has not been included on the SVHC list or classified
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32
