As hundreds of Richmond residents complained of respiratory ailments after Monday night’s fire at the Chevron refinery in Richmond, the Bay Area Air Quality Management District sent out a news release suggesting everything was fine.

Lab analysis from air samples showed levels of potentially toxic pollutants to be well under state standards “and not a significant health concern,” the district declared in a carelessly written statement.

It was seen as an environmental clean bill of health and juxtaposed in news stories with reports of residents lining up for health care and talking to attorneys about seeking compensation. The comparison left the impression that these were malingerers seeking to milk the system.

Perhaps that’s true for some, but probably not for most — we don’t know. What we do know is that the air district statement was incomplete and inaccurate.

For area residents who put up with daily pollution from the refinery and the anxiety and health effects resulting from Monday’s fire, the statement added insult to injury. Coming from an agency that is supposed to protect the public, it was particularly disturbing. Following a night of television coverage of thick black smoke spewing from the refinery, it also defied common sense.

It turns out that none of those test results measured smoke particulates in the air, which could very well have been the cause of respiratory problems, including asthma attacks, that residents reported experiencing.

That didn’t become clear until Bay Area News Group reporter Sandy Kleffman talked to Contra Costa’s public health director, Dr. Wendel Brunner, on Wednesday. He was the first public official to emphasize the shortcomings of the air district’s data. The district will eventually report particulate levels from the fire, but the usefulness of the findings will be questionable. Here’s why:

The agency regularly measures for particulates at just six locations around the Bay Area, one of which is in San Pablo, about three miles from the refinery. The samples are only collected for a 24-hour period once every six days.

In this case, the scheduled period happened to begin at midnight Monday, roughly six hours after the fire broke out and about an hour after shelter-in-place orders to residents had been lifted.

Eric Stevenson, a chemical engineer responsible for air district testing, told me the results from that sampling, which are still being analyzed, will be useful because particulates from the fire were probably still in the air long after it was contained.

But, when pressed, he acknowledged that it’s unknown whether the particulate fallout might have peaked before the test began or whether the lone location happened to be in the path of the smoke plume.

As for the test results reported Tuesday, those air samples were collected at downwind locations where air district officials believed they might see environmental effects. Unlike the particulate test, these tests measured gaseous pollutants.

The news release touted that the samples were tested for 23 compounds, and none exceeded state standards. It turns out that’s not so. A sample taken at the top of the El Cerrito hills had excessive levels of Acrolein, which is also a respiratory irritant.

The air district acknowledged the news release error after I asked about it Thursday. They later issued a public correction.

Stevenson said the result was not of concern because other findings from the same location were normal and Acrolein is often found at that level. But he pointed me to state data that actually showed the level Monday was unusually high.

Dr. Paul Blanc, chief of the Division of Occupational and Environmental Medicine at UC San Francisco, deserves credit for first noticing the district’s Acrolein test result. “These are at a level that could potentially raise concern,” he told me.

The air board should not ignore this, he said. “The answer is not ‘this is completely normal and, hey folks, there’s nothing there.’ “

While correcting some earlier misinformation, the district has yet to publicly acknowledge the minimal value of its particulates sampling.

This raises a bigger issue: The district must change how air samplings are collected and analyzed so that next time — and there will be a next time — the public can get useful and reliable information.

Daniel Borenstein is a Contra Costa Times columnist and editorial writer. Reach him at 925-943-8248 or dborenstein@bayareanewsgroup.com. Follow him at Twitter.com/borensteindan.