WAI'ANAE — Heavy smoke and ash from a brushfire that had already scorched 5,000 acres on the North Shore crossed over the Wai'anae Mountain Range and left Makaha Valley and Wai'anae residents in a cloudy fog throughout much of yesterday.

The state Health Department issued a smoke and dust advisory, urging residents to follow the guidelines of the American Lung Association — to stay indoors, turn on the air conditioner, limit exercise, drink plenty of liquids and refrain from smoking.

Wai'anae High and Makaha Elementary schools will be closed today because of the smoke and were closed yesterday at around 1 p.m. Makaha Surfing Beach also was closed yesterday.

By late afternoon, the smoke had begun to clear, due in part to strong trade winds.

While firefighters and helicopters worked to contain the fire on the North Shore side of the range yesterday, people along the Wai'anae Coast grew increasingly concerned about so much smoke.

Some residents complained that they weren't sure what they were supposed to do when no official word had reached the public by afternoon.

"They need to let the people know what's going on so they can know what to do if they've got asthma or respiratory problems," said Michael Randolph, security guard for the Wai'anae Public Library as he looked at his wristwatch, which said 1:30 p.m. "If you can't even see the mountain, then you know this isn't good. This air is horrible. We had one worker inside who couldn't hardly breathe. My eyes are starting to hurt me."

Wai'anae High School freshman Mary Ann Hansen, 14, fretted about how the smoke might be affecting her 2-year-old nephew as she hurried home from school.

"I'm worried about him," said Hansen, who also said she wasn't sure what people were supposed to do.

"The smoke is really bad," said Dessa Holbron of Makaha Valley Plantation, who wondered if residents should be evacuating.

Definitive answers were in short supply, and by early afternoon public safety officials were still trying to figure out what to do.

Shortly before 2 p.m., Honolulu Fire Department Capt. William Steinke from Station 26 in Wai'anae, along with several firefighters, established a command post outside the Makaha Valley Towers and began conducting air-monitoring tests.

They were soon joined by officials from the Department of Emergency Management, formerly O'ahu Civil Defense, who said they were working with city officials and the Red Cross to devise a plan of action.

Things began to fall into place.

Gavan Imamura, Red Cross disaster coordinator for O'ahu, advised those who were having breathing problems to seek shelter upwind from the smoke.

Exposure to smoke can irritate the eyes, nose, throat and lungs and cause anything from coughing and wheezing to severe reactions in people with chronic respiratory conditions.

"This is a developing situation, and we're aware of it," Imamura said. "The parties involved are assessing it to determine where would be the safest place for these people to go."

Fire Capt. Steinke said while the smoke had spread up and down the Wai'anae Coast, the main concern was the area inside Makaha Valley, where the smoke coming over the rise became trapped.

Officials considered whether to evacuate valley residents, but Wai'anae Command Battalion Chief Sigmund Oka said the decision was finally made to advise only those who were having breathing problems to evacuate on their own.

He said officials were initially concerned because of rising carbon monoxide and ash levels in the valley air. However, by around 3 p.m., trade winds bolstered by the approaching Hurricane Flossie — the cause of the smoke coming over the rise to begin with — had helped clear out some of the smoke.

"We took more readings and the level is actually more of a nuisance now," Oka said. "The level is low, and people should self-evacuate if they feel they should."

Bryan Cheplic, spokesman for the city's Emergency Services Division, said some people experiencing breathing problems went to the Wai'anae Coast Comprehensive Health Center.

By midafternoon, a shelter had been established at Nanakuli Beach Park by the American Red Cross and the Department of Emergency Management for area residents who wanted to escape the smoke and soot, according to HFD Capt. Terry Seelig.

At least some residents were wondering why it all took so long.

"The Health Department should have sent someone out here," said William Aila, harbormaster at the Wai'anae Boat Harbor. "This has actually been building up out here for three days, and it's finally reached this level of hazard. They dropped the ball on this one."

Reach Will Hoover at whoover@honoluluadvertiser.com.