Medical Surveillance After a Chlorine Release
A sodium hypochlorite line ruptures at a wastewater pretreatment area, releasing a chlorine cloud. Three workers are affected: Worker A was in the plume for about 30 seconds, coughed, and has a sore throat but is otherwise stable. Worker B was farther away, had no symptoms at the time, and wants to go home. Worker C was not in the plume but is a 28-year-old who has worn a respirator on this job for 14 months and has never had a medical evaluation for respirator use. The site has a clinic on contract and a written medical surveillance program. The supervisor wants to send A to the clinic, send B home, and keep C working because "C wasn't even near it."
1. Evaluate the supervisor's plan for Workers A, B, and C against the medical surveillance and emergency response expectations.
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The plan is partly right and partly wrong.
- Worker A: sending to the clinic is appropriate. A symptomatic exposure to chlorine warrants medical evaluation; document the exposure (duration, estimated concentration if known, symptoms) and send the record with the worker.
- Worker B: sending home without evaluation is not adequate. An exposed worker with no immediate symptoms can still develop delayed effects, and the program should provide for evaluation and follow-up rather than simply releasing the worker. At minimum, B should be evaluated or given clear instructions and a contact, and the exposure should be documented.
- Worker C: the supervisor's reasoning is wrong. C's issue is not this release - it is that C has worn a respirator for 14 months with no medical evaluation. Respirator use requires medical evaluation before use and at the intervals the program specifies. C should be removed from respirator use pending evaluation, regardless of proximity to the release.
The supervisor is treating "not near the release" as "no medical issue," which conflates the emergency exposure with the separate respirator medical clearance requirement.
2. What records and follow-up should the safety officer ensure are completed?
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- Exposure records for A and B: date, duration, symptoms, estimated exposure, and the medical evaluation and outcome.
- Incident report covering the line rupture, the release, and the response.
- Respirator medical evaluation for C, and a review of why 14 months passed without one - this is a program failure to correct, and likely affects other workers.
- Follow-up for A and B as directed by the clinic, with results communicated to the workers.
- Program review: confirm all respirator users have current medical clearances, and that the medical surveillance program covers the exposures this site actually produces.