the warning sign be more careful dbejte zvysene bezpecnosti in czech on a plywood wall informing about danger in hazardous area

accident area attention bezpecnosti building care careful careless caution construction czech danger dbejte emergency escape exclamation exit guidance hazard hazardous icon industry information isolated keep mark notice ostrava plywood rescue safety scaffolding security sign signage signal symbol text triangle urgency wall warning way wood yellow zone zvysene