Double the Bait, Reopen at Five
Late Friday a restaurant manager calls about German cockroaches in a commercial kitchen and wants treatment that night. The gel bait label reads: place 0.5 g spots, maximum 8 spots per 10 m2, do not reapply within 14 days. The residual product's label reads: crack-and-crevice application only; do not apply where food is exposed or on food-contact surfaces; re-entry interval 4 hours. Its SDS lists a flash point of 62 C, an acute oral LD50 of 500 mg/kg, and advises 'avoid breathing spray mist; use only with adequate ventilation.' Work cannot start until 11 p.m. and takes about three hours. The manager wants the kitchen reopened at 5 a.m., asks for double the bait rate, and wants baseboards behind the prep sinks sprayed because 'the last company did it.'
1. Which parts of the manager's request can be accommodated, and which cannot? Explain the legal basis for each answer.
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The label is the legal ceiling under both the federal Pest Control Products Act and Ontario's Pesticides Act. A client's request never enlarges it.
Cannot be done:
- Double the bait rate. Exceeding the labelled number of spots or amount per area is an off-label use - an offence - and it does not improve control. Oversized placements get avoided, dry out or become a surface contamination problem. Correct placement near harbourage, hinges, motor housings and void edges is what works.
- Spraying exposed baseboards behind prep sinks. The label says crack-and-crevice only and prohibits application where food is exposed or on food-contact surfaces. An exposed baseboard face is neither a crack nor a crevice, and it is in a food-handling area. 'The last company did it' describes someone else's offence.
- Reopening at 5 a.m. Work ends at 02:00; the 4-hour re-entry interval runs to 06:00. One hour short is still a violation.
Can be done:
- Reopen at 06:00 or later, or start earlier, or run a bait-only program with no re-entry interval that night.
- Require food and utensils to be covered or removed, surfaces cleared, and the manager's agreement recorded.
- Reapply bait no sooner than 14 days unless the label allows earlier inspection.
2. The technician asks whether he can rely on the SDS, which says only 'use with adequate ventilation,' instead of the label's stricter crack-and-crevice restriction. How should the supervisor answer?
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No. The SDS and the label do different jobs, and neither one substitutes for the other.
- The label authorizes use. It defines where, how much, how often, and the minimum PPE and re-entry interval. Anything outside it is an offence.
- The SDS communicates hazard. It exists for WHMIS and tells you about flash point, toxicity, first aid, spill response, handling and exposure controls. It contains no permission to apply a product in a place the label forbids.
The practical rule: where the two overlap, follow the more protective instruction, and where they conflict on use, the label governs. Here the SDS adds useful operational information - a flash point of 62 C means keep the product away from ignition sources in a hot kitchen, and the 'adequate ventilation' advice should shape how he works - but it changes nothing about where the product may go.
If the label is silent on a point, do not treat silence as consent for an otherwise aggressive method; use the least-risk approach consistent with the label and the SDS, and record the reasoning. If the label is genuinely unclear, call the manufacturer's technical line and document the answer before treating.
3. An hour into the job the technician feels light-headed and nauseated and can smell solvent strongly. What is the likely explanation, what should he do, and what controls should have been in place?
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Explanation. He is working in an enclosed commercial kitchen at night, likely with limited ventilation, using a solvent-based formulation and possibly an aerosol. Headache, dizziness and nausea in that setting point to solvent vapour exposure (pyrethroid actives themselves are low-volatility; the carrier is the usual culprit). Heat, poor sleep and working alone compound it. Treat it as an overexposure until proven otherwise, not as 'just the smell.'
Immediate actions: stop work; get to fresh air; remove contaminated gloves or clothing; wash skin with soap and water; sit down and tell someone. If symptoms persist, seek medical attention and take the label and SDS for the treating clinician. Do not re-enter to finish the job; reschedule, and notify the licence holder.
Controls that should have been in place: label PPE as a minimum (gloves, eye protection, and a respirator if the label requires one for this use); forced ventilation or open doors/windows with the gas equipment off and ignition sources controlled; smaller mixed quantities; no aerosol use in an occupied-adjacent kitchen; a lone-worker check-in; and a plan for stopping without financial pressure to finish.