View all News Focus on crystalline silica in ceramic products 30 July 2025 Salute e Sicurezza Materie: Protocolli settoriali Silice Cristallina Respirabile Sicurezza prodotti Salva nei preferiti INDEX 1. What is crystalline silica 2. Italian porcelain stoneware 3. Use of the product 4. Precautions and best practices during installation 5. Reference regulations 6. Legal warnings 1. What is crystalline silica Silica is the name used to refer to silicon dioxide (SiO2), which occurs naturally in two forms: crystalline and amorphous. Crystalline silica has an ordered structure and represents a family of minerals, the most common of which is quartz, the most abundant mineral in the Earth's crust. Quartz is found in many natural and man-made materials such as sand, granite, concrete, glass, ceramics and abrasives. Amorphous silica, on the other hand, lacks a definite three-dimensional structure and is associated with glassy phases. Crystalline silica reduced to particles smaller than 0.01 mm and dispersed as dust is referred to as respirable crystalline silica. Only this fraction is classified by the IARC (International Agency for Research on Cancer) as a Group 1 carcinogen. Similar characteristics are shown, for example, by hardwood dust, which is also classified as a Group 1 carcinogen. Potential exposure to respirable crystalline silica occurs only during mechanical operations (cutting, drilling, sanding) and is limited to technical personnel involved in these activities and during installation. These operations must therefore be performed by trained and qualified personnel. In contrast, amorphous silica, even when reduced to respirable particles, is not considered carcinogenic. Insights: NEPSI Guidelines Paper on crystalline silica - Confindustria Ceramica Master's thesis - Crystalline silica in the Italian ceramic industry: workplace, finished product, and installation "The role of silica in the ceramic industry" - Italian Ceramic Society - I.Cer.S. - April 16, 2025 2. Italian porcelain stoneware talian porcelain stoneware is a ceramic material produced from a mixture of natural raw materials, mainly clay (20-45%), feldspar (40-50%) and quartz (10-30%). The raw materials are mixed, spray dried, pressed and then fired at high temperatures, around 1200°C. During firing, the feldspars melt, leading to the consolidation of the material and the formation of an amorphous phase that accounts for about 63 (± 6)% of the final mass. Within this amorphous matrix: - quartz is present in small amounts, about 23 (± 5)%; - secondary crystalline phases occur, mainly mullite (4-10%) and partially fused feldspar residues. The mineralogical composition of the porcelain stoneware is homogeneous regardless of the size and thickness of the product: slabs and smaller formats maintain substantially equivalent percentages of quartz and crystalline phases. The production process, and particularly the rapid industrial firing cycle, characterized by high temperatures that trigger sudden phase transformations, gives porcelain stoneware its typical properties of high mechanical strength, low porosity and durability. Insights: Paper on crystalline silica - Confindustria Ceramica Master's thesis - Crystalline silica in the Italian ceramic industry: workplace, finished product, and installation Content of crystalline silica phases in porcelain stoneware Article CER 411 - CERAMIC SLABS AND TILES: same mineralogical composition 3. Product use Italian ceramic products for use in construction and furnishings, such as floor tiles, wall tiles and kitchen countertops, are characterized by high durability, with an estimated service life of well over 50 years. Under normal condition use, such materials ensure high safety standards for the end user. Possible exposure to respirable crystalline silica arises only during mechanical processing (cutting, drilling, sanding) and is limited to technical personnel engaged in such activities and installation. These operations must be performed by trained and qualified personnel in compliance with current occupational health and safety regulations, with the adoption of preventive measures such as: • Localized dust extraction systems; • Wet processing to reduce dust dispersion; • Use of appropriate personal protective equipment (PPE), such as filtering face masks; • Adequate ventilation of work environments; • Periodic monitoring of respirable dust concentrations. Insights: NEPSI Guidelines 4. Precautions and best practices during installation The responsible use of materials containing crystalline silica, including ceramic products, requires the implementation of appropriate preventive measures to be taken by qualified operators in compliance with national and union occupational health and safety regulations. Dust containing respirable crystalline silica can be generated during mechanical processing (cutting, drilling, grinding); the adoption of established best practices, including: Control of emission sources: use of wet machining technologies, -snap-cutting systems or localized vacuum systems to limit dust dispersion; Environmental controls: installation of forced ventilation and air exchange systems to maintain a healthy working environment; Personal protective equipment (PPE): use of certified filter masks appropriate for exposure levels assessed through the company's risk analysis that minimize the risk of inhalation; significantly reduces exposure to respirable dust. Intense, prolonged and repeated inhalation of dust containing respirable crystalline silica is associated with health risks, including respiratory diseases such as silicosis. Prevention can be implemented through continuous operator training, proper application of cutting techniques and safety protocols, and careful health surveillance. Non-professional do-it-yourself (DIY) activities are unlikely to expose people to high levels of dust for long enough to have an adverse health effects. However, it is recommended that the best practices established for professional operators also be followed in domestic or amateur contexts, and that the same basic precautionary measures be adopted to ensure safe use. For more information on how to reduce dust generation during do-it-yourself activities, see www.diywithoutdust.eu. Insights: NEPSI Guidelines IMA EUROPE Human Health Risk Assessment for Proposition 65 – Crystalline Silica in Ceramic and Glass Tile 5. Reference legislation EUROPEAN LEGISLATION Directive (EU) 2017/2398, which amended Directive 2004/37/EC, established an occupational exposure limit value of 0.1 mg/m³ (measured or calculated in relation to an 8-hour reference period) for respirable crystalline silica dust generated by machining process. This limit value was transposed into Italian law through Legislative Decree 44/2020, which amended Legislative Decree 81/08 on occupational health and safety. As required by Directive 2004/37/EC, the main obligations include: • Risk assessment for exposure to respirable crystalline silica; • Adoption of technical and organizational measures to limit exposure; • Provision of information and training to workers; • Health surveillance of exposed workers. In 2021, in line with the well-established practice of signing agreements/Protocols of Understanding in the ceramic tiles sector in Emilia-Romagna, a Region where more than 90% of Italian ceramic tiles are produced, the Region, Confindustria Ceramica, Acimac and the Trade Unions signed a "Protocol of Understanding" to ensure a practical and shared application of Directive 2017/2398 (transposed in Italy by Legislative Decree 44/2020). This active collaboration led to the development of three technical documents detailing the measures to be implemented for the practical application of the provisions introduced, ensuring an unambiguous interpretation of the regulations in force. Analyses are currently underway to morphologically and chemically characterize respirable crystalline silica dust generated in the ceramic industry. The work will conclude with the preparation of guidelines for information, training and refresher courses for workers exposed to respirable crystalline silica. AUSTRALIAN REGULATIONS As of July 2020, Safe Work Australia ha fissato un limite di esposizione a silice cristallina respirabile pari a 0,05 mg/m³. This means that workers must not be exposed to respirable crystalline silica concentrations above 0.05 mg/m3 averaged over an eight-hour workday within a standard five-day workweek. Since July 2024, in response to the growing cases of silicosis and silica-related diseases in engineered stone workers, the Australian government has banned the processing and installation of engineered stone in the form of panels and slabs and kitchen countertops (synthetic materials with a high percentage of quartz, up to 97 percent, bound by a polymer resin). CALIFORNIA REGULATIONS In California, employers must ensure that no employee is exposed to an airborne concentration of respirable crystalline silica greater than 0.05 mg/m³, calculated as an eight-hour time-weighted average. As of December 2023, in response to rising concern over cases of silica-related diseases in engineered stone workers, the California government introduced specific regulations for the processing of materials containing crystalline silica, including: • Development of silica control plans for all enterprises; • Implementation of wet processing techniques; • Health surveillance for exposed workers; • Mandatory training on exposure risks and safe processing practies. Engineered stones: these materials differ significantly from porcelain stoneware, both in production process and in chemical and mineralogical composition (they can contain up to 97% crystalline silica by weight). They are commonly manufactured by combining natural stone or other materials containing crystalline silica with adhesives, polymers, epoxies, resins or other binding materials (which can generate also VOC emissions) to form slabs. Insights: Engineered stone prohibition - Guidance for PCBUs - SEPTEMBER 2024 Working with crystalline silica substances - Guidance for PCBUs - JULY 2024 Emergency Silica Standard - What Employers Need to Know: Executive Summary Emergency Silica Standard: Information for Employers Emergency Silica Standard: Information for Workers Cal/OSHA Regulations – Title 8 – Chapter 4 – Subchapter 7 – Group 16 – Article 110 - § 5204. Occupational Exposures to Respirable Crystalline Silica Engineered stone prohibition - Guidance for PCBUs - SEPTEMBER 2024 6. Legal warnings The information on this site is provided for informational purposes only and does not constitute legal, technical or professional advice. The content related to occupational health and safety should not be considered exhaustive, nor a substitute for the obligations with applicable current regulations. Each work situation has specific characteristics that require targeted assessments in accordance with applicable regulatory requirements. The material on these pages are therefore general in nature and cannot be considered comprehensive with respect to the regulatory specifics of individual countries. Use of the information provided is at sole discretion and responsibility of the non-professional user and the employer, who remains primarily responsible for the safety of workers, personnel training and compliance with occupational health and safety legislation. Return to index
