Food Processing Industry Dust Collection

Introduction to Dust Control for Food Processing Industries

Food processing is a dusty business. From grain silos to bakeries to food packaging facilities, dust control is a critical consideration for the food processing industry.

The food processing industry as a whole produces many different types of dust. Some of the most common food processing dust types include fugitive grain dust from silo filling and grain transport; grain and flour dust from milling and grinding; corn starch and other powdered starches; dust from transporting or grinding dried nuts and legumes; dehydrated milk and egg products; sugar dust; and cocoa dust. The food processing industry also uses a wide variety of spices, flavorings and additives, some of which are hazardous in the concentrations workers are exposed to during food production.

Dust control for food processing is important from both a food safety perspective and a worker health and safety perspective. Uncontrolled food dusts create many different types of problems, including sanitation concerns, cross-contamination, microbial contamination, health issues for workers and slip-and-fall hazards. Dust control is also a regulatory consideration for food processors, who must comply with stringent food safety regulations from the FDA and USDA as well as occupational safety regulations from OSHA and NFPA. Failure to properly control food processing dust can expose companies to substantial fines, a greater risk of food recalls and even loss of FDA registration.

There are 32,000 food processing facilities in the U.S. alone, ranging from tiny local and regional bakeries to mega-processing plants employing up to 5,000 workers—and each one of these facilities has unique needs when it comes to dust control. Because the exact hazards and conditions vary so widely across the different parts of the food processing industry, mitigation solutions for food processing dust must be designed for the specific dust types, processes and environmental conditions at each facility. It is important to work with an engineering partner who can develop a holistic dust control solution that includes ventilation, dust containment and dust collection.

Dust Collection Challenges for the Food Processing Industry

The food processing industry faces several challenges when it comes to dust control. The exact risks and challenges depend on the ingredients and processes used. Most dust created by the food industry isn’t considered to be toxic or dangerous—after all, these are products intended to be ingested. But that doesn’t mean dust control isn’t important. Some of the most pressing concerns include the following.

Cross-contamination: Cross-contamination is a particular concern in the food industry. Many common food products provoke allergic reactions in susceptible people, and sometimes these reactions can be dangerous or even life-threatening. That makes it imperative to prevent cross-contamination of production lines with dust from other processes. Some of the most common food allergens found in food processing dust include wheat (gluten), nuts (peanuts, tree nuts, and other types), eggs (eggshell dust or dehydrated egg products), dairy (dehydrated milk), soy and sesame. Spices and food additives may also cause serious allergic reactions in some people. Beyond the allergen concern, it is simply undesirable to have food products contaminated with dust from other processes. Contamination with excess dust may impact food quality, flavor and desirability.

Microbial growth: The spread of food-borne pathogens is another very real concern for the food processing industry. Food products create an ideal breeding ground for many different kinds of microbes, including yeasts, molds and bacteria. While “dry” processes in the food industry (such as grain transport, cereal production and packaging, etc.) are not as susceptible to spreading pathogens as “wet” processes (like meat and dairy production), dry and powdered foods have been implicated in a number of food-borne illnesses, including salmonellosis and Enterobacter sakazakii. These microbes, along with many yeasts and molds, can thrive in environments with even very low levels of moisture. Packaged foods especially susceptible to microbial outbreaks include potato flakes and powdered milk and infant formula. However, many dangerous molds thrive on grain products such as corn and wheat. Dust control is important to reduce the spread of microbial pathogens in food production lines. Uncontrolled dust on window ledges, floors and other surfaces can become a breeding ground for dangerous yeasts, molds and bacteria. If this dust is allowed to re-contaminate production lines, pathogens can easily end up in the final product.

Combustion risk: Many of the dusts created during food processing are highly combustible. That means they can generate an explosion when allowed to concentrate in the air or inside a dust collection machine. In fact, some of the most common dust types in the food processing industry—including grain flours, powdered milk, corn starch, wheat starch, sugar, tapioca, whey, cocoa powder and many spices—are considered to be highly (The explosion at the Imperial Sugar refinery in Georgia in 2008 led to the passage of the 2008 Combustible Dust and Fire Prevention Act.) Special care must be taken when collecting combustible food processing dusts to minimize the risks of an explosion inside the dust collector.

Health hazards: While most bulk ingredients (such as grains, soy and potatoes) aren’t associated with health hazards, some substances used in the food processing industry are considered to be hazardous with prolonged and intensive exposure, especially by inhalation. These include spices, flavorings and additives that are not problematic when ingested in small amounts but can cause problems for workers in the food processing industry who are exposed to them all day long. For example, the compound diacetyl—a commonly used component of butter flavorings—has a well-documented history with lung disease. The condition in the industry has come to be called “popcorn lung.” Other chemical additives and flavorings used in the food processing industry can cause irritation of the lungs and mucus membranes or contact dermatitis. Cinnamon, for example, contains a volatile oil that can cause asthma, skin and eye irritation; it is often processed in special rooms due to the exposure hazards.

Nuisance dust: Just because a food dust isn’t considered to be toxic or hazardous doesn’t mean it’s not a problem. All food-related dust can still create health problems—such as lung irritation and aggravation of asthma symptoms—when inhaled. Some types of food dusts, especially flour and nut dust, can also trigger allergic reactions in susceptible employees, which can get worse over time with continued exposure. Uncontrolled dust of any type is also a housekeeping and sanitation consideration. 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.

Dust Control Regulations for the Food Processing Industry

The food processing industry is highly regulated. The Food and Drug Administration (FDA) is primarily concerned with food safety issues, including issues related to cross-contamination and microbial contamination, while the Occupational Safety and Health Administration (OSHA) develops regulations related to worker safety. Food processors also have to follow OSHA and National Fire Prevention Association (NFPA) standards for combustible dusts.

Food Safety: The Food Safety Modernization Act requires food processors to have controls in place to reduce cross-contamination of food allergens and prevent microbial contamination. These include preventative controls (which include 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 food recalls. Food processors are subject to annual inspections to ensure that they have the right controls in place. 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 food processing 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 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.

Combustible dusts: 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. In addition, manufacturers dealing with combustible dusts must follow National Fire Protection Association (NFPA) standards for prevention of fires and explosions. Food dusts fall 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. 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. OSHA’s Combustible Dust National Emphasis Program (NEP) outlines policies and procedures for inspecting workplaces that create or handle combustible dusts.

Other Regulations Specific to the Food Industry: OSHA has issued additional regulations for Grain Processing Facilities (1910.272) and Bakeries (1910.263). These regulations are primarily concerned with the high combustion risks of grain dust and flours, sugars and spices used in bakeries. Grain handling facilities must have a written plan for control of fugitive grain dust, including engineering controls and housekeeping measures to prevent the accumulation of dust both in the air on surfaces.

Considerations in Selecting a Dust Control Solution for Food Processing Dust

Engineering controls for food processing dust will generally include a mix of containment, ventilation and dust collection/filtration solutions. While the exact solution will vary depending on the dust type, specific processes, and layout of the facility and production lines, there are some general principles that apply across the food processing industry.

Collect dust as close to the source as possible to prevent propagation throughout the facility. This may involve enclosing certain processes or areas to enable efficient source capture and filtration.

Control airflow to prevent airflow and dust movement from dirtier parts of the process to cleaner parts of the process. In general, this means using positive and negative pressure zones to prevent air from moving from earlier processes (such as dry mixing) to later processes (such as packaging).

Each of the three major areas of the food processing industry have unique considerations when it comes to dust control.

Dust Control Solutions for the Food Processing Industry

RoboVent offers robust and innovative dust control solutions for all stages of food processing, including silo filling and dry mix, processing and packaging. We understand the regulatory pressures you are under and will help you design a system that will meet your needs.

Dust collection for food processing dust is not “one size fits all.” Our engineers will evaluate your processes and help you select the right dust collector and filter media. We can also design an industrial ventilation and makeup air solution for you to ensure optimal dust collection, reduce cross-contamination concerns and mitigate health and safety hazards.

RoboVent can also help you meet OSHA and NFPA regulatory requirements and safety guidelines for management of combustible dusts. We can conduct a dust hazard analysis (DHA) for your operations under the NFPA Combustible Dust Standard (NFPA 652) and put dust control systems in place to mitigate the risks of a combustible dust explosion from food processing dust.

Our experienced air quality engineers will work with you through the whole process, including needs analysis, system design and engineering, collector and ductwork installation, filter selection, HVAC system integration, startup and commissioning, and aftercare and service.

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