Occupancy and Commodity Classifications
Continuing Education Units (CEU): 0.10
Expected Duration: 1 Hour
This self-paced online course covers occupancy and commodity classifications as they relate to sprinkler system design. Occupancy classifications concern the use or intended use of a space. Commodity classifications relate to the materials, including packing materials, that may be present. Both can have a big impact on the characteristics of a fire that might occur, and therefore on the appropriate sprinkler system design.
Upon completion you should be able to:
- Identify the document that contains the requirements for classifying occupancies and commodities relative to sprinkler protection
- Explain the relationship between building code occupancies and sprinkler system standards
- Define occupancy and commodity, relative to sprinkler system design
- Explain key concepts, including: light hazard occupancy, ordinary hazard occupancy, extra hazard occupancy, class 1 through 4 commodities and group A, B and C plastic commodities
- Explain the relative burning characteristics of the different occupancy hazard classifications and commodity classifications
- List two examples of each occupancy, commodity and plastics group classification
- Explain how the classifcations is determined for a space with multiple occupancies or multiple commodity classes
Who Will Benefit
Anyone whose job involves designing, reviewing, evaluating or installing fire protection systems, including: designers, installers, engineers, electrical contractors, technicians, project managers, fire marshals, and architects.
- Prior to designing any sprinkler protection for a building, the occupancy classification of the space or commodity classification of the storage in the space has to be determined. Occupancy classifications are determined for areas where operations take place, such as a manufacturing floor, or where events take place, like an arena.
- The rate of heat release, continuity of combustibles and the environmental conditions all have an impact on burning, and if the classification isn't correctly assigned, sprinkler protection will be inadequate.
- Occupancies are broken into five classes, relative to the burning characteristics in the space:
- Light Hazard, such as an office or meeting room
- Ordinary Hazard Group 1, an example of which is a cannery or glass products manufacturing
- Ordinary Hazard Group 2, such as a distillery or dry cleaner
- Extra Hazard Group 1, where dust is typically present, such as a plywood plant
- Extra Hazard Group 2, similar to an automobile paint spray booth, or other spaces where flammable or combustible liquids are routinely present
- There can be more than one occupancy classification determined for a space. If different occupancies are separated, each occupancy stands on its own merit. But if it is a mixed occupancy within the same protected space, the higher occupancy classification prevails, and is used to determine protection criteria.
- Commodities are broken into four groups, but there is a different classification process for the storage of plastic commodities. The four commodity classifications, Classes I through IV, are based upon the relative amount of burning that can take place in a unit load.
- As the commodity class increases, so does the combustibility of the material in storage and the relative amount of plastics that are present in the unit load.
- There is also a separate classification for plastics, again relative to the ease with which they will burn. There are three groupings:
- A being the class that burns most easily. This group contains the plastics from which most toys and soda bottles are made.
- The Group B classification contains materials such as nylon and natural rubber.
- The Group C classification contains materials such as bakelite and melamine.
- Different commodities can be stored in the same warehouse or storage area. If this is done, and they are isolated, the protection criteria for each commodity stands on its own merit for that area. However, if the storage isn't segregated by classification, the highest classification applies throughout.