There has been concern in recent years regarding the possibility of risk to health arising from the use of certain ceramic materials. Walker Ceramics is constantly upgrading its safety information and we have our Material Safety Data Sheets available in our resources section and in our online shop under the various products we sell.
The following guidelines are designed to promote a safe and healthy working environment.
Observance of the following will ensure safety when handling all pottery materials including clays, glazes and colours.
- Eating, smoking and drinking should be prohibited in the workroom. Wash your hands thoroughly after each session.
- Workrooms should have readily cleaned, impermeable working surfaces and floors. Personal washing facilities should be nearby. There should be adequate ventilation.
- It is best to prevent dust rather than attempt to control it. Ware can be fettled or shaped whilst dry or such operations can be done with equal efficiency whilst leather hard or green and the surface finished with a damp sponge. Care must always be taken to avoid the generation of airborne dust.
Dust hazards can be minimized by the following:
- Immediately clean up any spillage of glaze or slip etc. since such materials when dry are a source of dust, particularly when tramped around the studio.
- Working surfaces, walls and floors should be thoroughly cleaned after use preferably by a wet method or with an industrial vacuum unit that meets Australian safety standards.
- Clean all equipment and utensils after use.
- Wet or damp processes are preferable to dry ones.
- Packages should be clearly labelled and securely closed to prevent particles being disturbed by draughts. They should be stored, opened and dispensed in a suitably ventilated area.
The following materials need particular care in handling : barium carbonate, borax, silica, zinc oxide, antimony oxide, chromium oxide, copper carbonate, copper oxide, manganese dioxide, nickel oxide, lead bearing glazes and all on-glaze colours.
Used packages should be carefully disposed of. With processes which cannot be controlled to eliminate dust, the following procedures are recommended:
- Protective clothing of a non dust retentive type should be worn. Terylene overalls or coats are recommended when using dry materials and impervious garments or aprons with wet materials. They should be cleaned regularly.
- Wherever possible all dusty work, including the spraying of glazes and slips, should be done in a suitable dust extraction compartment with filtered exhausts to outside atmosphere.
- If suitable dust extraction equipment is not available, disposable dust respirators, either toxic or non-toxic type, or approved respirators, should be used and a sufficient supply of replacement cartridges be readily available.
General Warning
Some of the materials stocked by Walker Ceramics could be poisonous if not used in the orthodox manner. The following materials have been classified as toxic. All packaging is labelled accordingly.
POISON S6 NOT TO BE TAKEN KEEP OUT OF THE REACH OF CHILDREN |
S5 WARNING NOT TO BE TAKEN KEEP OUT OF THE REACH OF CHILDREN |
||
CODE | MATERIAL | CODE | MATERIAL |
BA80 | Barium Carbonate | BA130 | Borax – Fine |
BA250 | Copper Carbonate |
Copper Compounds
When added to low lead solubility glazes, copper causes the solubility of the lead to be greatly increased, making the glaze unsuitable on vessels for use with foodstuffs and beverages.
Code | Raw Material |
BA250 | Copper Carbonate |
BA260 | Copper Oxide – Black |
Lead Free Glazes are all food and drink safe.
Fritted Lead Glazes
We do not sell or use red and white lead in any of our glazes as it is a dangerous material. A frit is a type of glass. It is a combination of materials which are melted together to render them insoluble and resistant to acid attack. They are therefore a means of introducing certain materials into a glaze that would otherwise be toxic. Glazes based on lead bi-silicate frits produce a shiny, durable finish and give brightness and clarity of colour when used in conjunction with oxides, stains, slips, etc. Some types of glazes may release lead and other metallic compounds when attacked by certain acids, notably fruit juices, vinegar and alcohol. To reduce solubility to acceptable limits we use frits which have a very low lead solubility to meet health and safety requirements. However even a safe glaze can be made unsafe by even minor additions of certain materials, notably copper (see raw materials) or by firing them above the recommended temperatures which are listed in the Walker Ceramics price list. Some of our decorative glazes would fail a metal release test and should not be used on the inside surface area of utility ware.
Cadmium Selenium and Copper glazes fall into this category. To achieve bright and vivid results care should be taken with their application and firing as they are by nature more sensitive than other glazes.
Powder Code | Liquid Code | Glaze Name |
ERR5185 | ERG5185 | Gold Lustre |
EUC5131 | ERC5131 | Flambe Red |
EUC5128 | ERC5128 | Bright Yellow |
Note
Safe glazes must be applied and fired under conventional conditions for them to be safe. These glazes should not be ingested or used without gloves. Walker Ceramics recommends the use of lead free glazes but the decision must nevertheless rest finally with the potter in any instance where the ware is intended for use with foods or beverages, especially so in oven-to-table or cooking ware. If any doubts are felt about the glaze formulation, firing, the possibility of contamination or the addition of such materials as copper compounds then certainly the wiser choice would be to use only lead free glazes at least on the inside or any surfaces that may come in contact with food.
Silica
Silica is a glassy material that is the most important constituent of pottery glazes and is an integral part of clay and many pottery materials. It is a hazardous material and must be handled with care. We feel that our customers must be aware of the properties of silica.
Technical Name: Silica Flour
Chemical Name: Silicon Dioxide SiO2
UN Number: Not Applicable
Ingredients: 96 – 100% Crystalline Silica
Risk Classifications
R20/R48 Harmful: Danger of serious damage to health by prolonged exposure through inhalation.
R36/R37 Irritating to eyes and respiratory system.
R43 May cause sensation by skin contact.
Safety
Long term exposure to respirable dust (silica) may cause lung disease e.g. Silicosis.
Respiratory protection must be to Australian Standard 1715/1716 and must be worn when handling or in close proximity.
Avoid dust contact with eyes. Safety glasses or face shield to Australian Standard 1337 must be worn at all times when handling or within close proximity.
Safety Phrases
S2 Keep out of reach of children.
S22 Do not breathe dust.
S36 Wear suitable protective clothing.
S38 In case of insufficient ventilation, wear suitable respiratory protection.
S39 Wear eye and face protection.
S26 In case of contact with eyes, rinse immediately with plenty of potable water and seek medical advice.
S46 If swallowed, seek medical assistance immediately and show physician the container or label.
Disposals or Spills
Avoid generating dust.
Dispose of in accordance with local government regulations.
For further information our Material Safety Data Sheets are available in in our resources section and in our online shop under the various products we sell.
The following agency will assist you in the case of poisoning with any substance:
Australian Poisons Information Centre
24 Hour Service 13 11 26
PROTECTIVE APPAREL
When working with clay it is essential that you protect yourself not only from the wet clay but also the products that you will use in conjunction with your clay. Over comfortable clothing you should wear an apron, preferably made from a waterproof material. You should wear good, strong yet comfortable footwear. When working with powders or spraying liquids, it is recommended that you wear an approved dust mask, preferably one for toxic substances as it has a very fine filtering material. When sanding and finishing dry or fired clay a dust mask is essential. Rubber gloves are useful to protect your skin from powders and raw materials when making glazes and colours.
Safety glasses or goggles are also a good item to have in your studio. They will protect your eyes from damage when handling powders or sanding dry clay surfaces.
APRON (Product Code HM10)
PVC waterproof aprons are designed to protect the clothing whilst working with both wet and dry materials.
GLOVES (Product Code HM45)
For use when handling hot ware, particularly useful for Raku firings. We stock Heat Resistant Kevler Gloves measuring 305 mm long.
MASKS
Whenever powders are being mixed, or colours sprayed, a mask should be worn.
To view our protective apparel visit our online shop.