Between 2013-2018, the distilleries industry has grown more than four percent each year. Much of this growth has been driven by the rise in micro-distilleries, which are now popping up in cities all across the United States. Micro-distilleries are small, often craft-style facilities that produce beverage-grade spirit alcohol in small quantities, usually in single batches. In contrast to large facilities that are typically located in rural areas, these operations – their barrel warehouses, mash rooms, and distilling equipment – are often located in re-purposed buildings in dense, populated urban centers.
To date, the distillery industry has been largely self-regulated in that fire safety codes specific to distilleries do not yet exist. Given their rural locations, where large distillery fires have occurred, they rarely spread beyond the facility. Now, due to the boom in micro-distilleries and the additional risks associated with their urban locations, the lack of clear guidance for these facilities is a growing concern.
Hazards Associated with Distilleries
To understand the hazards associated with distilleries, it helps to know a little bit about the process. Spirits (also known as hard liquor) is an alcoholic drink produced by the distillation of fermented grain, fruit, or vegetables. Distillation purifies the liquid into ethanol (the only kind of alcohol that is safe to drink) and increases its concentration by removing most of the water. The proportion of alcohol to water in spirits is commonly expressed as alcohol by volume (ABV). Spirits can contain between 20-90 percent ABV, but most, such as whiskey and vodka, are around 40 percent ABV.
The fire hazards associated with distilleries differ at various stages of the production process. The primary fire risk during the first two steps of the distillation process – the malting and mashing of the barley in preparation for fermentation – is the presence of dust from the milling of the grain, which can be highly combustible in large quantities.
During the fermentation process, the alcohol content is quite low, making fire risk relatively low at this stage. However, because fermentation creates a significant amount of carbon dioxide (CO2), any leaks or a failure in the extraction system could result in a toxic hazard if not properly vented.
Ignition is always a serious concern due to the flash point of ethanol created during the distillation process. At 55 degrees Fahrenheit (o F), the flash point of pure ethanol (the temperature at which it produces enough vapor to ignite in air) is well below room temperature while the flash point of a liquor such as whiskey or vodka, which contain about 40 percent ethanol (80-proof), has a flash point of 79o F, which is not much higher than typical room temperatures.
The still house, which is where the distillation process takes place, is usually a very warm room, which significantly increases fire risk. For context, consider that if ignited, a single pound of 80-proof liquor in a barrel can release 4,269 British Thermal Units (BTUs) of energy – the equivalent to 4.5 sticks of dynamite.
Once distilled, spirits are stored in oak barrels to mature, usually for a period of at least three years. As the spirits age, some of the flammable liquids in the barrels evaporate into the air. (Depending on who you talk to, this loss of spirits through evaporation might be referred to as the “devil’s cut” or the “angel’s share”). With flammable liquids stored in wood barrels in a potentially explosive atmosphere, it’s not surprising that many of the larger fires at distilleries have occurred in their barrel storage facilities.
According to the National Fire Protection Association (NFPA), the lack of distillery-specific codes is due to the distilleries industry’s history of lobbying and self-regulation. The Distilled Spirits Council of the United States (DISCUS) published its Fire Protection Manual to provide voluntary guidelines for new distilled spirits production plants including storage and warehouse facilities. The DISCUS manual references a number of NFPA codes and standards. However, authorities having jurisdiction (AJH) are not in a position to adopt and enforce the guidelines it contains because distillers may use them at their own discretion.
Absent clear regulations that address the hazards specific to distilleries, AHJ don’t have much to go on when determining how to enforce fire-safety practices. One issue is that the different uses within these facilities can make it difficult to assign occupancy types and classifications. For example, if a distillery contains a tasting room or offers tours to the public, is it an assembly occupancy or an industrial occupancy with hazardous materials?
The lack of commonly used codes also makes it difficult for small, independent craft distilleries – which are often started by relatively inexperienced producers – to understand all the risks associated with their industry, let alone how to mitigate them.
Insurance companies have done much of the early research on distillery fire safety, driven by massive losses in large distillery fires. FM Global, an American mutual insurance company, began researching fire protection and storage configurations for distilled spirits about five years ago and in 2017 started looking at palletized and rack storage of wooden barrels filled with 70 percent ABV liquid. And, Global Asset Protection Services (XL GAPS), provides two sets of guidelines related to distilleries – one that describes the recommended protection for distilled spirits stored in wood barrels (GAP 220.127.116.11) and another that provides recommendations for the remaining operations that take place in a distillery (GAP 18.104.22.168).
International Code Council (ICC) has plans to incorporate information on distilling into a new chapter of the International Fire Code (IFC) by 2021. And, the NFPA will explore how and where to include information specific to distilleries in its next edition planning process. In the meantime, let’s take a quick look at some of the operational practices distilleries can adopt to improve their fire safety.
Operational Tips for Making Distilleries Safer
In the section above, we described the primary fire hazards associated with distillery operations. Here are some things distilleries can do now to help mitigate them.
General Best Practices
- Practice good housekeeping throughout the facility and barrel house by minimizing the storage of combustible materials and immediately cleaning up any spills.
- Implement preventive maintenance for all equipment, including boilers and conveyors, and conduct regular inspections and nondestructive testing of fermenting tanks and pumping systems.
- Strictly prohibit smoking throughout the distillery and barrel house, and install no smoking signs in highly visible areas.
- Train all employees about how to safely handle, clean up, store, and dispose of alcoholic beverages. A Safety Data Sheet (SDS) should be provided to each employee and can provide the basis of your training.
- Train all employees on how to respond to fires, including how and when to use fire extinguishers, where the evacuation routes are located, and how to get any visitors or customers in the distillery to safety.
Operational Best Practices
- Never leave a still unattended while in operation.
- Do not allow filling or emptying barrels in the barrel house, and never store empty barrels there.
- Do not store alcohol in metal drums unless they are equipped with adequate pressure relief valves.
- Always keep the distilling area well ventilated to avoid any potential buildup of alcohol vapors.
- Do not charge the still boiler with wash at alcohol concentrations above 40 percent to reduce explosion risk.
- The distilled alcohol receiver should be kept at as low of a level as possible to reduce the risk of a spill should the container tip over.
- Use a receiver that has a small filling opening to reduce vapor escape.
- To reduce the risk of accidental overflows, put the receiver in a large, nonflammable, ethanol-resistant container large enough to contain at least an hour’s worth of output should the receiver spill or leak.
- Dilute alcohol to below its flash-point before placing it into storage.
Consult the Fire Experts
At Koorsen, we pay attention to industry trends and stay on top of all relevant fire safety codes. With a growing number of craft distilleries in our communities and the lack of fire safety regulation, our experts can help new and existing distilleries protect their businesses from the risks inherent in their operations. Contact Koorsen today to better understand, assess, and mitigate your fire risks to keep your employees and customers safe.