METROPOLIS, Ill. — Honeywell plans to lay off nearly 230 workers at its southern Illinois plant as it undertakes upgrades ordered by regulators to make the site able to withstand an earthquake or tornado.

Honeywell says the layoffs will affect 125 hourly and 103 salaried workers at the Metropolis plant, which helps make nuclear fuel. Roughly 100 employees will be kept for work unrelated to production at the plant.

The laid off employees will be paid through Sept. 21 and receive benefits through the end of that month.