Flammable Ice Cream? Yes.
Addressing Flammable Liquid Hazards in Unexpected Places
NFPA Journal® online exclusive, October 2007
By Phillip Bistany
Ice cream is an American favorite and one of the most successful dairy-based products of all time. According to the U.S. Department of Agriculture Economic Research Service, approximately 1.3 billion gallons of ice cream were produced in the United States in 2004. The average per capita consumption during this same year was approximately five gallons.
On the surface, the thought of ice cream and its production sounds fairly innocuous. It is frozen and then it melts when exposed to ambient temperatures. The basic ingredients are milk and cream, sweeteners and additives to stabilize, texturize, and harden it. Nothing hazardous there. But what about the flavorings?
According to the International Ice Cream Association, approximately 50 percent of the top fifteen ice cream flavors are vanilla or have a component of vanilla in them (i.e. chocolate chip, vanilla fudge ripple, etc.). Did you know that most vanilla flavorings are (ethyl) alcohol-based with flashpoints below 100º F (37 º C), which classifies them as Class I flammable liquids per NFPA 30, Flammable and Combustible Liquids? In fact, many flavoring products used in the production of ice cream are liquid, alcohol-based formulates possessing flashpoints, which classify them throughout the flammable – combustible liquid range. In addition, most flavoring products are shipped in plastic containers ranging from single to 55 gallon (208 liters) or greater storage drums.
The case study that follows shows a real-life example of how an unexpected fire hazard, in this instance the improper storage of flammable liquids, can be controlled using a linear-stepped risk analysis approach (including hazard recognition, evaluation, remedy, decision and implementation measures) in conjunction with appropriate fire code application (in this case, NFPA 30), as well as dealing with unexpected obstacles which may be encountered along the way.
Loss history involving flammable & combustible liquids
Per the 2006 “Selections From U.S. Fires In Selected Occupancies” report published by the NFPA Fire Analysis and Research Division, an estimated annual average of 1,100 structural fires in industrial and manufacturing properties involving flammable or combustible liquid or gas products as the first ignited items were recorded during 1999 – 2002 period. The estimated annual direct property damage as a result of these fires was $112 million. Similarly, the NFPA report for “Storage Properties” for this same time period, showed an estimated 800 annual structural fires involving flammable or combustible liquid/gas products as the first ignited item. The resulting annual direct property damage was $22 million.
Perhaps the best illustration of the large-loss potential of these liquids is what many consider to be the hallmark fire loss involving flammable liquid products. On May 27, 1987 a fire started at an automotive paint distribution plant when 8 to 10 cartons of 1-gallon (3.7-liter) metal containers storing flammable liquid product fell from a load being moved by a lift truck. The resulting flammable liquid pool was ignited via a spark from the lift truck’s electric motor and quickly spread to adjacent bulk storage of flammable liquid products in metal and plastic containers.
The ensuing fire rapidly spread in this noncombustible building and the steel roof began to collapse within five minutes of the fire’s ignition, despite the presence of automatic sprinkler protection. Even with automatic sprinklers operating and fire-fighting efforts from local fire departments, the fire breached a fire wall and within approximately 30 minutes, the entire 180,000 square feet (16,722 square meters) building was involved. The resulting real and personal property as well as debris removal costs were estimated at $49 million (1987 dollars).
As a result of this loss, the fire protection community began to look closer at the hazard potential presented by flammable and combustible liquid fires.
A New England company manufactures ice cream for retail sale throughout the eastern U.S. One location manufactures 100 percent of the company’s ice cream products and is comprised of two separate buildings.
The primary facility is approximately 200,000 square. feet (18,580 square meters), and is a one and part two-story building, comprised of mixed, but mostly noncombustible and masonry noncombustible construction consisting of either light steel panel on steel frame or masonry block exterior walls and mostly exposed steel deck on steel bar-joist roofs. This building houses the ice cream manufacturing operation as well as raw ingredient and finished product storage areas and corporate offices. Storage, manufacturing and support areas are intermixed within the building and - due to a lack of rated, fire cutoff walls - are considered a single fire area per NFPA 30.
An estimated 75 percent of this building is protected via control-mode automatic sprinklers. Sprinkler systems are considered of acceptable area/density design per NFPA 13, Installation of Sprinkler Systems with the most demanding systems protecting mixed commodity, dry-goods storage materials in double-row storage racks to 16 feet (4.8 meters) with a 21-foot (6.4-meter) ceiling height.
Several areas of this building are refrigerated using ammonia-based refrigeration equipment. Included in these areas are a few small raw ingredient storage coolers as well as several freezers totaling approximately 50,000 square feet (4,645 square meters) The freezers are used to store finished ice cream products, considered Class I storage commodities per NFPA 13, in multiple-row racks to 25 feet (7.6 meters) with a 30-foot (9.1-meter) ceiling height. The freezers are conjoined and constructed of approved metal-faced insulation panels on steel frame. All freezers are non-sprinklered, but contain automatic heat detection fire alarms.
The secondary building is one-story, 80,000 square feet (7,432 square meter) constructed of masonry-noncombustible construction possessing masonry block exterior walls and exposed steel deck on steel bar-joist roof. Mixed commodity raw ingredient and packaging materials are stored in double-row racks to an estimated 20 feet (6-meter) with a maximum 30-foot (9.1-meter) ceiling height. At the center of this building is an estimated 25-foot (7.6-meter) by 110-foot (33 meter) cooler used to store refrigerated ingredient products. The building is fully protected by control-mode automatic sprinklers of appropriate area / density designs per NFPA 13. The cooler is protected by a dedicated anti-freeze automatic sprinkler system.
The plant has a private water supply which consists of a 2,000 gpm (7,570 lpm) at 100 psi diesel fire pump taking suction from an underground 400,000 gallon (1,514,164 liter) suction tank. This pump and tank supply all automatic sprinkler systems as well as ample private yard hydrants for the plant. A paid fire department is located three miles from the facility. The plant has an automatic fire alarm system consisting of sprinkler waterflow, sprinkler valve tamper, heat and smoke detection, manual fire alarms, fire pump, and ammonia supervisory alarms monitored by central station.
The ice cream manufacturing process itself is considered standard to the industry and consists of basic blending, mixing, pasteurizing & homogenizing, freezing and packaging operations.
Recognition of the flavoring exposure
A loss prevention survey initially revealed several cases of flammable-based flavoring products in gallon plastic containers, a relative small quantity, stored outside the primary production area of the plant. This prompted the company’s safety officer to question whether special storage considerations should be given to the “other” flavoring products present at the plant.
Given the recommendations that would evolve from this survey, the company asked its local Authority Having Jurisdiction (AHJ) to review the surveys’ conclusions. After reviewing the situation, both the local AHJ and the state fire marshal concluded that the present situation represented a severe, uncontrolled fire hazard and mandated that measures be taken to control the hazard per NFPA 30 by working through the company’s insurance carrier’s loss prevention department.
Evaluation of the hazard
A study was completed to determine specific flavoring products used, when they were used (some flavorings were used only during specific times of the year), maximum quantities on site, where each product was normally stored and the flammability rating per the applicable Material Safety Data Sheet (MSDS).
The study revealed the following hazard characteristics:
Applying NFPA 30, Chapter 6 “Container and Portable Tank Storage,” it was clear these products were not properly stored or protected as two primary requirements of section 6.5.2, General-Purpose Warehouses, were not met:
The conclusion reached was the storage of the flavoring products presented a severe, large fire loss hazard to this plant. Since this plant was the company’s sole manufacturing plant, not only was its real and personal property at risk but its entire business as well.
Remedies to mitigate the hazard
Working in concert with the company and a food industry construction consultant, the company’s insurance carrier offered the following potential remedies:
All of these options had advantages and disadvantages when considering functionality, manufacturing (process) flow and costs, but there was one unexpected factor which was not initially contemplated by any party.
This was the fact that some flavoring products were stored in refrigerated areas and some were not. The company’s product quality personnel concluded that refrigerated flavorings could not be stored in a non-refrigerated environment without affecting the taste of the finished ice cream products they were used in. This created the dilemma of requiring redundant versions of any chosen remedy, one for refrigerated product and one for non-refrigerated product.
After consultation with the company’s flavoring suppliers and their in-house product quality department, the company concluded that storing flavorings not normally requiring refrigeration in a refrigerated environment would not affect the finished ice cream products’ taste. Therefore, all flavorings could be stored in a refrigerated environment if necessary.
For the options offered, the requirement of a refrigerated environment as well as personnel safety concerns involving material handling between buildings during periods of inclement weather eliminated the possibility of storing product in an outside trailer or shed.
The option of storing flavorings in listed flammable liquid cabinets was not accepted based on practicality, as the company had several thousand gallons of flavoring product on site at any one time and NFPA 30 limits the quantities, which can be stored in cabinets in a single fire area to 360 gallons (1,362 liters) (three cabinets with 120 gallons (454 liters) in each).
The resulting decision was to store all refrigerated flammable and combustible liquid flavorings in a rated flammable liquid storage enclosure while storing non-refrigerated, combustible liquid products in existing rack storage areas and providing them with the required in-rack sprinklers and horizontal barriers.
As a refrigerated environment was a requirement, the simplest solution would be to store this product in listed, pre-engineered, pre-fabricated flammable liquid storage locker enclosures as allowed by NFPA 30. One drawback was the limited locker size available, which meant that to meet NFPA 30 requirements, two lockers would be needed at an estimated cost of $64,000. This cost was independent of the added cost it would take to meet the non-refrigerated combustible product rack storage protection requirements.
Therefore, the company decided that the most cost-effective solution would be to construct a rated flammable liquid inside storage room from the ground-up, in an existing cooler in the main manufacturing building for all flammable and combustible flavoring products.
As an interim loss mitigation strategy, all flavoring products would be stored in the detached, raw material warehouse building to eliminate the fire hazard to the manufacturing operations in the main plant.
An overview of the room’s basic design characteristics required per NFPA 30, section 6.4 included:
No mechanical ventilation and damage-limiting construction was required by NFPA 30 as no dispensing operations were planned within the room nor any storage of Class IA flammable liquid products expected.
As the room was used to store food-grade product, the wall and ceiling assemblies needed to contain insulation and fascia components, which not only met NFPA fire-rating requirements, but also met FDA standards for food occupancy usage. Eventually, insulated wall and ceiling panels meeting all requirements were identified and approved by the AHJ, but additional time and research were necessary to accomplish this.
It took 10 months and approximately $90,000 to complete the inside flammable liquids room project. When compared to the insurance carrier’s estimate of $70 million total insured value being exposed to a fire loss associated with this previously unrealized hazard, the expenditure seemed well worth it to all parties. A major risk of loss, from a real & personal property as well as business interruption and potential market share loss standpoint for this company had been significantly mitigated.
The principal lesson of this case study is that flammable and combustible liquids can be present in large quantities in unexpected occupancies. Whether it be flavoring products involved with ice cream manufacturing, solvent, cutting or hydraulic liquid media used in metalworking occupancies or storage of products such as hand sanitizing products (which are mostly ethanol based) in a cleaning supplies distribution warehouse, awareness must be maintained for the fire hazard of all liquid materials introduced into an occupancy.
Careful consideration must be taken regarding the proper storage and protection of flammable liquid materials to mitigate their large fire loss potential with the primary strategies being isolation, containment and suppression. As seen in this case study a linear–stepped risk analysis approach, one which encompasses NFPA standards and codes application along with location specific needs works well in achieving this goal.
Failure to act when flammable liquids are present can severely expose a company’s ability to stay in business.
In this Section:
|Lessons Learned from the Minneapolis Bridge Collapse
An interview with Minneapolis Fire Chief Jim Clack.
|Haunted Houses and NFPA 101
The Life Safety Code is as much a part of Halloween as creaking staircases and ghostly sounds.
|Flammable Ice Cream? Yes.
Addressing flammable liquid hazards in unexpected places
|‘Live Free or Die’ State Listens to Its Youth
The sale of fire-safe cigarettes only becomes law in October