As distiller go about their day-to-day work and longer-term planning, a small number of questions hover over every choice. How do I make the best product? How do I do so in the most efficient, economically sound way?
An additional top-level consideration that can be overlooked is safety: How do I ensure that I’m making, bottling, and sending out product in the safest way possible?
Right there alongside quality and the bottom line, safety must be a priority in distillery planning and operations. Daily hazards at a distillery can include exposure to heights and the potential for falls, explosible grain dust, flammable vapors, scalding liquids, broken glass, crushing hazards, trip hazards, and repetitive-motion injuries.
Outfitting from the Outset
Many safety considerations fall within the realm of equipment choices. A well-planned distillery includes safety in the budget and day-to-day processes. Infrastructure and distillery planning go hand-in-hand with safety.
Naturally, the first consideration to come to mind for many is the presence of ethanol in high volumes and high concentrations—and potentially in vapor form, if there’s a leak in the still. You should consult with an expert when selecting equipment to reduce the danger of leaks—both liquid and vapor—and the possibility of ignition in the case of a leak.
You should also consult with local code enforcement authorities, as there tends to be a patchwork of varying regulations from one municipality to another; sometimes, one location is unfeasible while another five miles away is a perfect fit.
In general, to mitigate the potential danger of an ignition related to a vapor leak, you can rely on intrinsically safe systems to eliminate possible ignition sources. For example, you can use air-operated diaphragm pumps in the distillery rather than the centrifugal pumps often seen in breweries.
Sombrero of Death
The Sombrero of Death concept, presented by the engineering and design firm Dalkita at several distilling conventions, is a valuable framework for considering the most dangerous areas around the distillery.
If the flammable vapor in the still were to leak out from an unknown place, it creates a potential zone a little higher than the still, a little wider than the full vapor path from still to condenser to the ground, and then much wider along the ground because the vapor will settle at ground level.
In effect, this potential zone is a tall, wide, sombrero-shaped area that must be free of electrical devices that could spark and ignite a vapor leak. That may mean designing around this constraint and finding other places for electrical outlets, lights, and other fixtures. It may also mean using explosion-proof motors and lights where necessary, such as on an agitator for the still.
Grounding is essential for tanks containing spirit to prevent static discharge, which can ignite ambient vapor in the headspace of the tank and in the surrounding area.
Grain handling is another often-overlooked danger. Because grain dust is an explosion hazard, milling is often done in a separate space from the distillery. This space may have a dust-collection system, explosion-proof components (where electrical systems are required), and a regular cleaning schedule to prevent any accumulation of dust.
Contents Under Pressure
Another important infrastructure aspect is the proper sizing and placement of vacuum-relief and pressure-relief valves on tanks.
Distillers should consult with an engineer to properly calculate the demand their standard operations might put on a tank. To properly equip these vessels—such as fermentors, stills, and other tanks—the engineer will consider how quickly they can be emptied, filled, or the amount of pressure that may build during fermentation.
A properly sized vacuum-relief or pressure-relief valve (sometimes available in combination) can prevent tanks, seals, or other fittings from rupturing if a vessel becomes over-pressurized. That can happen, for example if a fermentor clogs, or if it’s improperly configured to create a closed system. Proper pressure relief can help prevent dangerous and potentially explosive equipment failure.
Vacuum relief, on the other hand, can help you avoid a negative-pressure situation in a tank. This occurs most frequently when pumping out of a fermentor or other closed container without allowing for displacement of the volume being removed, either with ambient air or applied air/CO2 pressure. In that state, a vessel without proper vacuum relief can implode.
The Culture of Safety
Besides equipment choices and workspace design, another very large chunk of safety—to navigate the day-to-day realities that can make a workplace unsafe—depends on culture and training.
PPE, or personal protective equipment, is a part of any distiller’s regimen. Day-to-day expectations at the distillery should include, at a minimum, hard-toed shoes and long pants. There are also specific operations with a need for eye protection, ear protection, work gloves, or heat-resistant gauntlets—gloves that extend to protect the forearm as well as hands. More intensive work, such as entering and repairing tanks, can require even more involved equipment, such as a harness and retrieval system or a respirator.
Also, as a part of the day-to-day distillery workflow, distillers should consider ergonomics and repetitive-motion injuries. While these concerns can exist all over the building, the packaging area is a place where some of these issues are magnified, combining a work environment that involves standing all day while performing the same motions hundreds and possibly thousands of times in a shift.
While some of that can be mitigated—for example, by providing anti-stress rubber mats in places where employees stand all day—much of it is cultural. To avoid repetitive-motion injuries in an area such as bottling, a thoughtful owner or manager might have employees rotate positions periodically, take frequent small breaks, and ensure that they know how to stretch to minimize risk of injury.
The Occupational Health and Safety Administration (OSHA) also requires that employers have a variety of programs in place, and that they document employee training for workplace hazards. These mandatory trainings include (but are not limited to) using PPE and hearing and respiratory protection, responding to chemical spills or bloodborne pathogens, and lockout/tagout procedures.
Ultimately, employees should understand that safety is always the first priority, and it's incumbent on distillery operators to reinforce that mindset rather than encourage risk-taking to save a few minutes
A too-common example of this is having a worker standing on a pallet, raised high via forklift to stack or unstack something , or to reach piping or other infrastructure far up on the walls or ceiling. That may save time (versus pulling a pallet down for stacking/unstacking) or a few dollars (by not having to buy a taller ladder), but at what potential cost?
Many of these types of day-to-day practices, while widespread, put employees at unnecessary risk and are OSHA violations that can lead to significant fines.
It Starts at the Top
Ultimately, distillery safety comes down to company culture. If production metrics are the be-all end-all when defining a successful shift or a strong quarter, then employees will absorb the message that they should prioritize those numbers—potentially at the expense of their health and well-being.
However, if the importance of worker safety is prioritized and discussed, with a goal of continuous improvement just as in other top-level considerations like quality, then the distillery team will be encouraged to think critically about how to ensure that everyone goes home unharmed every day.