Fruit and Crop Ripening

This chapter establishes requirements for ripening processes involving the introduction of ethylene gas to promote the maturation of fruits, vegetables, and other crops.

1601 — General

1601.1 Scope. Ripening processes where ethylene gas is introduced into a room to promote the ripening of fruits, vegetables and other crops shall comply with this chapter.

Exception: Mixtures of ethylene and one or more inert gases in concentrations which prevent the gas from reaching greater than 25 percent of the lower explosive limit (LEL) when released to the atmosphere.

1601.2 Permits. Permits shall be required as set forth in Section 105.6.

1601.3 Ethylene generators. Approved ethylene generators shall be operated and maintained in accordance with Section 1606.

1602 — Definitions

1602.1 Terms defined in Chapter 2. Words and terms used in this chapter and defined in Chapter 2 shall have the meanings ascribed to them as defined therein.

1603 — Ethylene Gas

1603.1 Location. Ethylene gas shall be discharged only into approved rooms or enclosures designed and constructed for this purpose.

1603.2 Dispensing. Valves controlling discharge of ethylene shall provide positive and fail-closed control of flow and shall be set to limit the concentration of gas in air below 1,000 parts per million (ppm).

Worked example

Scenario: A produce distribution center plans to convert an existing storage room into an ethylene ripening room for bananas.

Explanation: The room must be specifically designed and constructed to contain the ethylene gas, including considerations for ventilation, sealing, and structural integrity, and be approved by the fire code official for this specific use.

1604 — Sources of Ignition

1604.1 Ignition prevention. Sources of ignition shall be controlled or protected in accordance with this section and Chapter 3.

1604.2 Electrical wiring and equipment. Electrical wiring and equipment, including luminaires, shall be approved for use in Class I, Division 2, Group C hazardous (classified) locations.

1604.3 Static electricity. Containers, piping and equipment used to dispense ethylene shall be bonded and grounded to prevent the discharge of static sparks or arcs.

1604.4 Lighting. Lighting shall be by approved electric lamps or luminaires only.

1604.5 Heating. Heating shall be by indirect means utilizing low-pressure steam, hot water or warm air.

Exception: Electric or fuel-fired heaters approvedfor use in hazardous (classified) locations which are installed and operated in accordance with the applicable provisions of NFPA 70, the International Mechanical Code or the International Fuel Gas Code.

Worked example

Scenario: In a new fruit ripening room, the electrical lighting and control panels need to be installed.

Explanation: All electrical equipment within the ripening room, including lights, switches, and outlets, must be explosion-proof or rated for hazardous (classified) locations to prevent any potential spark from igniting the ethylene gas, as per Chapter 3.

1605 — Combustible Waste

1605.1 Housekeeping. Empty boxes, cartons, pallets and other combustible waste shall be removed from ripening rooms or enclosures and disposed of at regular intervals in accordance with Chapter 3.

Worked example

Scenario: A ripening room frequently accumulates empty fruit cartons and wooden pallets after product deliveries.

Explanation: To comply with housekeeping rules and Chapter 3, these combustible wastes (empty boxes, cartons, pallets) must be removed from the ripening room at regular, frequent intervals, such as daily, to minimize fire load and hazards.

1606 — Ethylene Generators

1606.1 Ethylene generators. Ethylene generators shall be listedand labeledby an approved testing laboratory, approved by the fire code official and used only in approved rooms in accordance with the ethylene generator manufacturer's instructions. The listing evaluation shall include documentation that the concentration of ethylene gas does not exceed 25 percent of the lower explosive limit (LEL).

1606.2 Ethylene generator rooms. Ethylene generators shall be used in rooms having a volume of not less than 1,000 cubic feet (28 m3). Rooms shall have air circulation to ensure even distribution of ethylene gas and shall be free from sparks, open flames or other ignition sources.

Worked example

Scenario: An architect is specifying an ethylene generator for a new ripening facility.

Explanation: The selected ethylene generator model must bear a label from an approved testing laboratory, indicating it has been evaluated for safe operation in ripening rooms. The fire code official must also approve its use, and it must be installed and operated strictly according to the manufacturer's provided instructions.

1607 — Warning Signs

1607.1 When required. Approved warning signs indicating the danger involved and necessary precautions shall be posted on all doors and entrances to the premises.

Worked example

Scenario: A building contains a newly constructed suite of three ripening rooms.

Explanation: Prominent, approved warning signs indicating the hazards of ethylene gas and necessary safety precautions must be clearly posted on all doors leading into each of the ripening rooms and at the main entrance to the suite.

Frequently asked questions

What kind of rooms are required for ethylene gas ripening?

Ethylene gas must only be discharged into approved rooms or enclosures specifically designed and constructed for the purpose of crop ripening.

What precautions are needed regarding ignition sources in ripening rooms?

Sources of ignition must be controlled or protected in accordance with Chapter 3 and the specific requirements of this chapter to prevent accidental ignition of ethylene gas.

Are there specific requirements for ethylene generators?

Yes, ethylene generators must be listed and labeled by an approved testing laboratory, approved by the fire code official, and used only in approved rooms following the manufacturer's instructions, with the listing evaluating concentration levels.