ARTICLES
A clean room is an environment in which the presence of suspended microparticles of dust is reduced to a minimum, with strict control of hygiene levels, temperature, air pressure and humidity, which must be within the limits imposed by current regulations (GMP and ISO 14644).
Initially developed for microelectronics laboratories, clean rooms have since spread to the pharmaceutical, chemical, aerospace, mechanical engineering, hospital and food industries.
The air supply in the clean rooms is via a low-intensity laminar forced ventilation system located on the ceiling, to avoid the formation of turbulence that could deposit microparticles in the environment; return grilles located in the lower part of the walls provide for the expulsion of air outside.
The quality of the injected air is guaranteed by special HEPA (High Efficiency Particulate Air filter) type filters, consisting of microfibre sheets that have the task of blocking microparticles in the air.
Technical Standard ISO 14644-1 defines the purity of the air in a clean room on the basis of the number of microparticles of different sizes present per cubic metre, with a classification ranging from ISO 1 (the highest level in terms of air purity) to ISO 9.
A factor of fundamental importance in the realisation of a clean room is the materials and technical solutions used in its construction.
In fact, the air quality control requirements do not only depend on the air supply, but also on the certainty that the materials used do not tend to disperse microparticles, that they are impervious to chemical and bacteriological agents, that they guarantee perfect moisture tightness to prevent the onset of mould, that they are easy to wash and sanitise by resisting frequent and aggressive cleaning cycles, and that they have a high level of fire resistance.
The need to provide a product that could effectively meet all these requirements led to the practice and production of Isopan insulation panels, in their various dimensional and material conformations.
Available in different thicknesses and sizes, they feature a range of solutions to ensure that the air quality required in a clean room is maintained.
Another consideration of prime importance, especially at a time like the present when environmental sustainability has been compounded by uncertainty over energy supply, is the characteristic of Isopan panels to maintain a stable internal temperature in clean rooms, allowing energy savings and a consequent reduction in costs and environmental pollution.
Isopan panels are manufactured in continuous line production facilities, allowing time and cost optimisation to cope with even large orders.
Isopan insulation panels are insulated sandwich panels consisting of several layers, similar to a sandwich.
They generally consist of two rigid outer parts, made of metal coated with PVC or other materials, combined with a central insulating layer. The type of material used for the insulation layer and its thickness influence the performance and weight of the panel.
The outer metal cladding can be made of galvanised steel, stainless steel or coated with protective alloys such as AZ (zinc aluminium) or ZM (zinc magnesium), aluminium or other metals.
The production process of Isopan panels guarantees a solid joint between the metal cladding and the internal insulation, thus contributing to the creation of construction elements of high rigidity and mechanical strength, in relation to their lightness; all characteristics that make Isopan panels easier and more convenient to transport, store and assemble, ensuring a reduction in operating costs.
The central part in Isopan panels performs the dual role of a rigid element (in conjunction with the outer cladding), and of thermal insulation. The materials used can be polyurethane foam (PUR or PIR), mineral wool and the new LEAF insulation formulation.
Closed-cell polyurethane foam is anigroscopic (does not absorb water molecules from the environment), lightweight, with excellent resistance to mould and fungal attack, dimensionally stable, with excellent mechanical performance, including compressive and flexural strength.
Mineral wool, whether rock or glass, is ideal for passive building protection as it is non-combustible. It also offers excellent thermal insulation and maximum levels of acoustic insulation.
Available with different thicknesses of insulation material, Isopan panels can meet all requirements for maintaining the required temperature inside clean rooms, while offering a range of construction solutions and choice of cladding materials that cover all air quality requirements.
Awareness of the need for increasing attention to sustainability issues, combined with the goal of reducing environmental impact as much as possible, led to the creation of LEAF technology panels in which no halogenated flame retardants, potentially harmful to the environment, are used.
The new LEAF technology, for the production of the interior insulation material, allows a reduction in heat loss of up to 20% for the same thickness, lowering the thermal conductivity value of the polyurethane foam and allowing lower thermal transmittances than standard insulation. All this translates into reduced costs and environmental pollution.
Another advantage of using LEAF technology panels is the possibility of obtaining credits within the LEED and BREEAM certifications, for projects where special attention is paid to sustainability and the environment.
LEAF panels are also the first in Europe with a Declare label, which communicates the origin of the product, the materials it is made of and instructions for its correct disposal at the end of its life cycle.
LEAF Isopan panels have obtained the maximum reaction to fire certification in Europe for polyurethane panels, called B-s1, d0.
European legislation provides for a classification of building materials that takes into account flammability, smoke production and dripping.
The B-s1,d0 certification establishes that Isopan panels with LEAF technology have high fire resistance (class B; A covers completely non-flammable materials, such as metals and glass), with the lowest production of harmful fumes in the event of fire (class s1), and no production of molten droplets (d0).
The most immediately appreciable feature of Isopan panel dry junction systems is the simplicity of assembly, which leads to a reduction in the time required for implementation, resulting in lower costs.
The dry construction system also entails lower costs for site preparation and does not require a water supply, thus avoiding water wastage.
The advantages of the jointing systems in Isopan panels are not only economic; they meet the need for clean rooms to guarantee high air quality, preventing the formation of moisture stagnation at the joints, as well as guaranteeing the absence of thermal bridges that could lead to the growth of mould and bacteria.
The importance of adequate connection solutions between the panels is to ensure that with the frequent cleaning of the clean rooms, water and/or other liquids cannot be deposited between the joints, resulting in mould growth.
COLD SOLUTIONS products, Isopan solutions for temperature- and atmosphere-controlled environments, with the Isofrozen/Isofrozen HT panels offer four different types of panel joints to effectively meet the different requirements of the production process.
Effective clean room cleaning also depends on the type and shape of the surfaces to be cleaned and sanitised; some processes use acids or solvents that can corrode surfaces. When disinfecting the clean room, disinfectants in aqueous solution with a contact time on surfaces of several minutes are used; water penetration must therefore be prevented by using suitable building materials. Similar problems can occur when cleaning the clean room with surfactant solutions.
To this end, different types of external claddings have been designed with Isopan panels; in the Cold Solutions product range, Isopan offers smooth or slightly profiled finishes, designed to facilitate washing operations and avoid the accumulation of dust, liquids or particles, which can lead to the proliferation of microorganisms.
The surface layer can be made of standard polyester (PE), PET on a pre-painted steel base or PVC film. All surface finishes provide excellent resistance to corrosion and moisture.
It is also possible to carry out surface treatments after installation to ensure strict control of the environment from an antibacterial and hygienic point of view.
Such systems are ideal for the elimination of all pathogens, while also removing air pollutants, odours and VOCs (Volatile Organic Compounds) continuously and completely safely.
Isopan Cold Solution was created with the aim of providing designers, technicians and construction companies with a complete system for the construction of clean rooms and cold rooms, in which, in addition to the panels in their various conformations in terms of size, insulating material and surface finish, there are all the accessories required to guarantee the necessary control of air quality, temperature, humidity and pressure.
Connecting elements between vertical walls and floors and ceilings were designed to ensure the structural continuity necessary to prevent the accumulation of liquids, particles and dust.
For the connection of internal walls, Frigo Base solutions are available, connections for internal partitions and Cold Rooms, and Frigo Plus, with high-quality connections for Cold Rooms and processing chambers.
Fixing accessories with T /Omega profiles for suspended ceilings are available for ceiling systems. Made of white painted aluminium, they are fire-resistant and have plastic-coated steel nuts that act as thermal breaks.
To summarise, the modern design, construction and operational management of working environments such as clean rooms or cold rooms, in which, in addition to the problems common to every building (costs, compliance with construction site deadlines), the maintenance of precise environmental conditions is essential, finds in Isopan products the ideal partner to meet all the requirements that this type of project requires, allowing rapid execution times, containment of energy costs, compliance with building safety regulations, and environmental sustainability.
Marta Lupi, materials engineer and R&D Project Manager at Isopan, is involved in research projects aimed at identifying new product and process solutions. She works closely with universities, research centres and strategic partners for innovation.
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