Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
1
Is any of this happening now?
Call 911
Call emergency services now if someone has:
Severe trouble breathing, blue or grey lips, or worsening wheezing
Collapse, confusion, extreme drowsiness, or a seizure
Severe chest pain or coughing up pink, foamy fluid
Swelling of the mouth or throat, drooling, or inability to swallow
Vomiting blood, severe abdominal pain, or a rigid abdomen
Severe eye pain, loss of vision, or a large chemical burn
Do not attempt a rescue in an enclosed chemical area without trained emergency support.
Elsewhere, use the local poison information service or emergency number.
And for anyone, someone who:
you believe has taken an overdose or swallowed something poisonous
Other emergency signs, for anyone
Someone who is struggling to breathe, gasping, choking, or cannot get words out
Someone who has chest pain, tightness or pressure lasting more than a few minutes
Someone who has sudden weakness or drooping on one side of the face or body, slurred speech, or sudden confusion
Someone who is unconscious, or cannot be woken
Someone who is bleeding heavily and it will not stop with firm pressure
Someone who has had a seizure that will not stop, or does not wake up afterwards
Someone who has lips or skin that look pale, blue, grey or blotchy
2
Is any of this happening?
Be seen today
Contact a poison centre promptly after swallowing a pool chemical, breathing concentrated fumes, or having ongoing symptoms after skin or eye contact.
In the United States, Poison Control is available at 1-800-222-1222.
3
Does any of this apply?
Book an appointment
Arrange routine follow-up if a cough, wheeze, skin wound, eye irritation, or swallowing discomfort is not steadily improving.
Difficulty swallowing that appears weeks or months later also needs assessment.
The article also says
Leave the contaminated area before calling if fumes are present.
Every sign above is quoted from the sofidex article on Swimming pool cleaner poisoning. If you are not sure, err upward — it is always reasonable to be checked.