Dust Collection for Confectioners and Candy Makers

• Artificial sweeteners (stevia, sucralose, saccharin, aspartame)
•  Starches (cornstarch, tapioca powder, rice flour, gums and other dry ingredients)
• Spices and flavorings (cocoa powder, cinnamon, cloves, nutmeg, ginger, mace, etc.)
• Powdered milk, whey powder
•  Food additives, preservatives and emulsifiers 
• Nuts

A lot of the dust in the candy-making process happens up front when sugar and other dry ingredients are being dosed, mixed and moved. Dust is also created during panning, sugar coating or at the end of the process when candy pieces are finished. Specifics depend on the recipe, process and equipment, but dust-creating processes may include: 

•  Bulk material handling, transport and conveyance
• Measuring/pouring/dumping
•  Dry mixing/batch mixing/sifting 
• Panning/candy-coating 
• Tablet mixing/pressing 
• Starch moulding 
• Nut chopping
• Topping/dusting 
• Cutting/cracking 
• Packaging (box filling, bag filling, carton filling)

• Combustion risk: Combustion is perhaps the most serious risk for confectioners. Many of the products used in candy making—including sugars, cocoa powder and starches—are highly combustible. That means they can generate an explosion when allowed to concentrate in the air, in enclosures and conveyance systems, or inside dust collection equipment. A dust control system must be used to prevent ingredients and process dust from accumulating in the air and especially within enclosed spaces such as conveyors.
• Filter selection: Candy dust can be especially tough on filters. Granulated sugar is highly abrasive, putting extra wear on filter media. Sugar dust may also be heavy, wet and sticky, causing it to cake on filters in a thick crust that makes it difficult to pulse off.
• Food safety: Confectioners must consider food safety when it comes to dust control, including both microbial growth and cross-contamination. Uncontrolled candy dust creates an ideal breeding ground for many different kinds of microbes, especially if the environment is warm and humid. Candy makers must also have systems in place to prevent cross-contamination between different products. This is especially important when working with ingredients that are common food allergens, such as nuts (peanuts, tree nuts) commonly added to chocolate candy bars. Spices and food additives may also cause serious allergic reactions in some people and can contaminate the area with microbes. 
• Food quality and presentation: Beyond the allergen concern, contamination with excess dust may impact candy quality, flavor and desirability. It is especially important to control dust during the packaging process, including box filling and bag filling; excess dust in or on the packaged product is highly undesirable from a consumer perspective. Panning and tablet press processes require special consideration to contain their dust and to prevent dust from other parts of the facility from contaminating the production equipment and products. 
• Worker health and safety: Many spices and additives are also dangerous when inhaled, and some may cause skin or eye irritation. Cinnamon, for example, contains a volatile oil that can cause asthma and skin and eye irritation; it is often processed in special rooms due to the exposure hazards. And uncontrolled dust of any type is a housekeeping and sanitation consideration. Dust build-up on walking/working surfaces can create slip-and-fall hazards for workers. 
• Odor levels: Flavors, colors, spices and other additives create odors that can be undesirable in confectionery processing. Depending on the ingredients and processes, emissions may include gases or vapors that must be controlled along with the dust. For example, some flavors, oils and spices release volatile organic compounds (VOCs) that are unpleasant or dangerous in high concentrations. They can also cause flavor contamination to other products, such as mint flavor being “absorbed” into chocolate, hard candy or gummies; some mint flavors can even affect glues used in packaging materials. These situations will require a solution that is able to control vapors and gas-phase emissions as well as dry particulate.
• Humidity levels: Humidity control is essential for many candy-making processes. Some candy products are hygroscopic, meaning they will absorb moisture from the air—which can prevent processing, change the texture, cause stickiness and make them prone to spoilage. At the same time, parts of the candy-making process, such as cooking, add humidity to the environment. A dust control system must be paired with a humidity control system to keep humidity levels within the proper range and reduce caking of wet dust on the filters for optimized processing efficiency.

• Combustible dusts: Candy-making dust falls under NFPA 61, Standard for the Prevention of Fires and Dust Explosions in Agriculture and Food Processing, as well as NFPA 654, Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing and Handling of Combustible Particulate Solids. Combustible dusts are regulated under OSHA’s General Duty Clause (Section 5(a)(1)) with additional requirements under the Hazardous Locations (§1910.307), Hazard Communication (§1910.1200) and Housekeeping (§1910.22) standards. OSHA’s Combustible Dust National Emphasis Program (NEP) outlines policies and procedures for inspecting workplaces that create or handle combustible dusts. Dust collection systems for food processing dusts must also meet NFPA 68, Standard of Explosion Protection by Deflagration Venting, and NFPA 69, Standard on Explosion Preventing Systems. 
•  Food Safety: The Food Safety Modernization Act requires all companies in the food industry, including confectioners, to have controls in place to reduce cross-contamination of food allergens and prevent microbial contamination. These include preventative controls (such as control of airborne dust, prevention of dust build-up on surfaces and in production lines, and sanitation of equipment and surfaces) as well as processes for food safety evaluation, problem identification and mitigation, and product recalls. Companies that do not comply with FDA food safety requirements are at risk of large fines or even suspension of their registration. 
• Nuisance dusts: Many candy dusts fall under the OSHA definition of “nuisance dusts,” which are regulated under the general particulate matter concentration limits set by OSHA. The general limit for “Particulates Not Otherwise Regulated” (PNOLs) is 15 mg/m3 (8-hour TWA limit) for total particulate and 5 mg/m3 for respirable particulates. Employers must also follow general housekeeping standards (OSHA 1910.22, Walking-Working Surfaces) to prevent accumulation of dust on surfaces.
• Flavoring Substances: OSHA has not developed specific Permissible Exposure Limits (PELs) for most chemicals used in candy making and food processing. However, because of the safety concerns for workers exposed to fine respirable dusts and volatile organic compounds (VOCs) produced by many chemical flavorings and additives, OSHA has issued a Safety and Health Information Bulletin titled Occupational Exposure to Flavoring Substances: Health Effects and Hazard Control. While these recommendations are not binding, OSHA strongly suggests that companies where workers are exposed to potentially dangerous food additives put engineering controls in place, including appropriate ventilation, isolation of processes (such as batch mixing) that produce dust or fumes, and access control for areas where these processes occur. Individual states may also have more stringent regulation of flavoring substances, such as California’s Proposition 65.

• Dust collection and filtration: A cartridge-style dust collector is a practical and efficient choice for many candy-making processes. Cartridge-style dust collectors have a small footprint per CFM compared to other styles of dust collectors, such as baghouse. They also have a wider range of filter options to collect even very fine dust, such as confectioners’ sugar or aspartame. An efficient pulsing system must be used to pulse excess dust from fabric dust collector filters. In some cases, a wet collection system may be advised; talk to a system designer to find out which type of dust collection system is right for you. 
• Filter media selection: Filter selection is critical when collecting sticky, hygroscopic dusts produced by the candy industry. Sugar, cocoa, cornstarch and many other candy and chocolate ingredients are hygroscopic, meaning they readily absorb moisture from the air. In a humid environment, these dusts may cake or form a crust on filters. A washable filter media can extend filter life considerably in these situations. PTFE coatings can also be used to help sugar dust shed more efficiently from filters. 
• Enclosure/source capture: Many candy-making processes (e.g., batch mixers, tablet press, candy coating line, etc.) are easily enclosed to contain dust for source capture. If the process cannot be enclosed, it is possible to create a custom hood to draw dust away from the production line as it is created. Positive and negative pressure zones can also be used to prevent dust from earlier processes and conveyor systems from propagating into areas where candies and chocolates are finished and packaged. 
•  Combustion mitigation: Special care must be taken when collecting sugar and other combustible dusts to minimize the risks of an explosion inside the dust collector. The dust collector should be equipped with a deflagration system including explosion vents for safe venting of excess pressure and isolation valves to prevent pressure waves from propagating back into the facility if an explosion should occur.
• VOCs and odors: If emissions include VOCs or other gas-phase and vaporous emissions, after-filters may be needed. Activated charcoal after-filters can be added to collect gases and vapors that are not captured by fabric filters. 
• Humidity control: Humidity control will be required for most confectioners. The dust collection system should be paired with an effective humidity control system to keep humidity within required ranges for the process. Humidity control will also improve the effectiveness of the dust control system.