One man was hospitalized and another required medical treatment after they were exposed to chlorine vapors yesterday at a Campbell Industrial Park business.

The incident was reported about 1:50 p.m. at the BEI Hawai'i bleach plant on Kaomi Loop.

A plant employee reported hearing a container "blow a cover" and noticed a strong chlorine odor, said Honolulu fire spokesman Capt. Kenison Tejada.

Two men were exposed to the vapors.

One was taken to St. Francis Medical Center-West, where he was in good condition yesterday afternoon.

A second employee was treated at the scene.

Tejada said the area was evacuated, but there were no other reports of injuries.

Cheryl Soon, BEI spokeswoman, said the plant's manager shut off a valve to the tank and notified emergency response teams with the city, state and federal governments.

She said the plant was closed yesterday and will be tested today before employees are allowed to return.

Soon said an investigation into the cause of the leak is under way.

"Assuming we do go in (today), they'll be checking all of the lines to see what the issue was," Soon said.

"We decided that the best thing to do was to close the plant for the day and then we'll go in and see what if any repairs will need to be done or what might have caused it."

Yesterday's incident occurred at the same plant where a massive sulfuric acid spill produced a huge plume of toxic gas above Campbell Industrial Park on Thanksgiving Day 1999.

Workers at neighboring Chevron Refinery discovered that sulfuric acid, estimated at 35 tons, had leaked into a concrete trench and mixed with chlorine to cause the plume.

Chevron notified BEI officials, but the incident was not reported to the federal National Response Center until 11 hours later.

Following an investigation by the Environmental Protection Agency, BEI agreed to pay $236,000 in fines.

Yesterday's incident was reported to the National Response Center within seven minutes, Soon said.

Reach Curtis Lum at culum@honoluluadvertiser.com.