STONEFRUIT
Fumigation Tour Southern Fumigation Services
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BY SCARLET ROXBY VALUE CHAIN FACILITATOR, STONEFRUIT
n October 20, WA Stonefruit held a tour of the methyl bromide (MB) facilities at Southern Fumigation Services in Cockburn Central. Fourteen guests joined the two Adrians and Kylie to understand the inner workings of the fumigation process for produce coming from the Perth Markets. The tour provided an understanding of MB requirements, variability and longevity of produce being fumigated, and gave growers peace of mind that Adrian and Adrian handled the produce professionally to provide customers with quality produce. The following provides notes from the discussion and tour.
TABLE 1. FUMIGATION RATES FOR 2HR PERIOD. Temperature (°C)
Rate of methyl bromide (g/m3)
21+
32
17–21
40^
10–17
54
^ Best results
are in a dormant state with limited respiration and movement. When produce arrives for treatment, the temperature of random pallets is measured with dosage rate being worked out based on the lowest temperature measured. Produce is brought up to 17°C in the fumigation room with a fan circulating air evenly.
process takes two hours, with an additional hour to vent MB gas before the room can be opened. The MB concentration reading is recorded manually 30 minutes after the MB release and 1 hour before the end of fumigation process, after which the gas is vented from the room. MB must be below 5 parts per million (ppm) in the fumigation room before produce can be safely removed. If fumigation is occurring at night, the room can be scheduled to be a cool room on completion of fumigation.
Methyl bromide is a controlled substance.
Pallets are spread out to assist air/ fumigant flow. MB concentration is monitored, recorded, and checked throughout the treatment, using three sensors equally distributed across the fumigation room. The fumigation
Most pallets have a same day turnaround time for fumigation, dependent on the time the produce is received, as fumigated produce will not be released until authority to do so is received from Quarantine WA (QWA). Southern Fumigation Services have the capacity to fumigate 45 pallets a day. f TOUR group listening to Adrian and Adrian (left in yellow and orange) as they talk about the fumigation process.
Here are a few notes from the discussion and tour.
Fumigation process Successful MB fumigation is dependent on an ideal combination of dosage rate, treatment time and treatment temperature. If one of these factors is incorrect then fumigation is not effective. (Successful fumigation = dosage rate x treatment time x treatment temperature). Produce must be greater than 10°C as a minimum and less than 32°C as a maximum, with the ideal range between 17°C – 20.9°C (see Table 1). At lower temperatures, the respiration of insects is reduced, therefore uptake of fumigant by insects is lower. Below 10°C insects WA Grower SUMMER 2021
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