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OSHA & YOUR BREWERY: Confined Space Safety


Your partners for all your confined space needs:

  • Emergency Breathing Equipment
  • Personal Protective Equipment
  • Fall Protection
  • Gas Detection
  • Lone Worker
  • Ventilation

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The Brewers Association (BA) provides a helpful, consistent guideline for Brewers Association members to use when working in and around confined spaces in the brewery. Employers and employees must work together to assure a safe workplace.

Frequently Asked Questions

1. What exactly is a confined space?

The OSHA confined space standard 29CFR1910.146 defines a confined space as the following: • An area large enough and so configured that an employee can bodily enter and performed assigned work, and • Has limited or restricted means of entry or exit and • Is not designed for continuous occupancy. • A space must meet all three of these characteristics to be considered a confined space.

2. What confined spaces typically exist in a brewery?

Examples of confined spaces typically found in breweries include bright tanks, fermenters, grain bins, silos, mash tuns, kettles, yeast propagation tanks, liquor tanks and trailers used for fresh or spent grain. In addition, larger breweries may have sump pits, utility vaults, water treatment tanks and other confined spaces.

3. What is the difference between a confined space and a permit required confined space?

When additional hazards may be present the space may be further classified as a permit required confined space (PRCS). OSHA defines a PRCS space as a confined space that has at least one of these additional hazards: • Contains or has the potential to contain a hazardous atmosphere • Contains a material that has the potential for engulfing an entrant • Has an internal configuration that might cause an entrant to be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross section. • Contains any other recognized serious safety or health hazards. Many types of brewery confined spaces will contain carbon dioxide and may also be oxygen deficient. Other serious safety hazards could include powered rakes, stir paddles, agitators, clean in place systems (CIP), inlets to allow entry of liquids or grains and other mechanical or physical hazards such as heat or steam. Performing work in the confined space can also introduce hazards into the space that cause the space to be classified as a PRCS. Examples could include welding in the space, bringing in electric power tools, using strong acids or bases or other hazardous chemicals.

4. What are the alternatives to a permit required confined space entry?

When all of the hazards of a PRCS can be eliminated from outside the confined space without entry, the space may be eligible for reclassification. Reclassified spaces can be entered without an entry permit. The entry still requires careful planning, employee training, as well as monitoring and control of the hazards. An experienced and knowledgeable person should evaluate the reclassified space and certify that all hazards have been eliminated from the confined space before entry occurs. Should conditions change or hazards arise during the entry the employee must exit the space immediately and the employer must re-evaluate the space. Work performed or chemicals brought inside the reclassified space can create a hazard, for example, welding or using cleaning chemicals will require the space be treated as a PRCS. If the cleaning chemicals are not hazardous, for example, dilute detergents or caustics, then the space may remain reclassified. These hazards must be evaluated to determine the proper classification of the space. Proper personal protective equipment should be utilized regardless of the classification of the confined space. As an example, if mash tun with a powered rake must be entered the grain could be removed and the tun rinsed clean, the powered rake could be locked out, the steam jacket emptied and cooled, and any piping connected to the tun could be disconnected to prevent entry of liquids. In this case all of the hazards have been eliminated without entering the mash tun except for the potential lack of oxygen. Direct fired vessels could also have an additional hazard of carbon monoxide from combustion gases. The atmospheric hazards can be addressed using mechanical ventilation of the mash tun to provide fresh air. The mash tun must then be tested from outside the confined space with a multi-gas meter to confirm and document that oxygen levels are acceptable and then the space can be re-classified from PRCS to a non-PRCS and entry can proceed. Remember though that introducing any further hazard in that space causes the space to again be classified as a PRCS.

5. What if our employees are just sticking their head inside a hatch to look inside the confined space?

OSHA considers a confined space entry to have occurred when any part of the employee’s body breaks the plane of the opening to the confined space. Consider the case of a fermenter with an atmosphere deficient in oxygen because of high concentrations of CO2. An employee looking into this space could be quickly rendered unconscious with their head inside the tank and their torso outside. Another example is reaching into a confined space to clean the area under the manway where the CIP system may not reach. Employees typically reach into the manway to perform the cleaning and often stick their head inside to check the progress of the cleaning. These situations are considered a confined space entry by OSHA and all of the same precautions must be taken as if the employee had completely entered the vessel.

6. Is there some way our brewery can eliminate the need to enter confined spaces?

The safest way to manage confined spaces is to not enter them in the first place. Clean in place systems allow cleaning and sanitation without entry; inspections can be performed from outside the vessel using mirrors and flashlights, video cameras or fiber optic camera systems. In cases where spray ball(s) for the CIP is not reaching all areas of the tank then portable cleaners can be purchased that can be placed through the manway opening for additional coverage. When placing standpipes, flavoring or hop bags, a long handled gripper tool can be used to perform the work from outside the confined space. Cleaning can be performed with long handled scrubbers. If the brewery does not have the expertise to safely perform and manage a confined space entry a contractor experienced in this type of work may be an option.

7. How is the atmosphere in a confined space tested to ensure ventilation has controlled the contaminants inside?

The atmosphere inside a confined space must be tested using equipment that can detect the hazards that may be present. Multi-gas meters that detect oxygen, carbon monoxide, lower explosive limit and toxic gases such as hydrogen sulfide are typically used to test a confined space prior to entry. For brewery applications the meter must also be capable of detecting carbon dioxide. Any meter used for confined space entry must be properly maintained, calibrated and bump tested prior to use to ensure it is functioning properly. OSHA requires that confined spaces first be tested for oxygen levels, then combustible gases, and finally any toxic gases or vapors in that order. Atmospheric testing must be performed from outside the vessel, multi-gas pumps can be equipped with a battery operated pump and tubing to allow testing inside a confined space without entry. The space should be tested from top to bottom and side to side to ensure there is not any stratification of the atmosphere inside the tank. Users of these meters must be properly trained, due to the length of tubing used and the response time of the sensors, the meter can take up to a few minutes to accurately provide a reading at each measurement point. All measurements should be recorded to document the space is safe to enter. The confined space should be tested periodically during entry to ensure the space remains safe for entry. One means to accomplish this is to require entrants to wear a small portable gas detector with alarm that can monitor oxygen and carbon dioxide levels (and any other contaminants that may be present) to ensure the space remains safe for entry during work. The multi-gas meter used to initially test the confined space can also be used to take periodic measurements. Additional types of air sampling may be needed if the work inside the space can generate hazardous contaminants or gases.

Learn more about management of confined spaces in breweries.