Well, that articles first two paragraphs indeed say exactly the opposite of what you are claiming.
The rest is paywalled. So, you are trying to match my five cites with one that does not say what you claim it does?
Ok, here is the American cancer soc:
and here is the British Medical Association:
## People at risk of coronary heart disease should avoid exposure to secondhand smoke
Even without future studies or replications of these findings1 the data are sufficient to warrant caution regarding exposure to secondhand smoke.2 23–24 Clinicians should be aware that such exposure can pose acute risks, and all patients at increased risk of coronary heart disease or with known coronary artery disease should be advised to avoid all indoor environments that permit smoking.3 5 16 Additionally, the families of such patients should be counselled not to smoke within the patient’s home or in a vehicle with the patient. In addition to its impact on heart disease, exposure to secondhand smoke causes lung cancer in non-smokers, respiratory infections and asthma in children, and even death in exposed infants.2 17 30 As the US Surgeon General and the US Community Preventive Service Task Force have noted,2 23 24 much of this important health risk is preventable by the implementation of comprehensive smoke-free policies similar to the policy that was implemented in Helena for six months
Exposure to secondhand smoke from burning tobacco products can cause sudden infant death syndrome, respiratory infections, ear infections, and asthma attacks in infants and children, and coronary heart disease, stroke, and lung cancer in adult nonsmokers ( 1 ). There is no risk-free level of secondhand smoke exposure ( 2 ). CDC analyzed questionnaire and laboratory data from the National Health and Nutrition Examination Survey (NHANES) to assess patterns of secondhand smoke exposure among U.S. nonsmokers
https://jamanetwork.com/journals/jama/article-abstract/198892
People at risk of heart disease should avoid secondhand smoke because it increases the risk of acute myocardial infarction (MI), the US Centers for Disease Control and Prevention (CDC) warns in a commentary in the April 24 issue of the British Medical Journal ( BMJ . 2004;328:980-983).
The warning accompanied a study concluding that smoking bans at work and in public places may be associated with reducing morbidity from heart disease ( BMJ . 2004;328:977-983).
And hell, lets bring in Ireland too, which talks about Helena:
But if New York - as well as other cities and municipalities - is ever tempted to rescind its smoking ban, it should look at the goings-on in Helena, Montana. The citizens of Helena voted in June 2002 to ban smoking in all public buildings - including restaurants, bars and casinos. Soon after, doctors at the local hospital noticed that heart-attack admissions were dropping. So, in conjunction with the University of California, San Francisco, they did a study to measure the potential short-term effects of a smoking ban.
Helena is a perfect place for such a study: relatively isolated, with enough people in the region (66,000) for a meaningful population sample, and only one cardiac-care hospital within a 60-mile radius.
So it was easy to control the study sample and methodology: if you get a heart attack in Helena, there’s only one place to go for treatment.
The study showed two trends. First, there was no change in heart attack rates for patients who lived outside city limits.
But for city residents, the rates plummeted by 58 per cent in only six months.
“We know from longer-term studies that the effects of secondhand smoke occur within minutes, and that long-term exposure to secondhand smoke is associated with a 30 per cent increased risk in heart attack rates,” says Stanton Glantz, a professor of medicine who conducted the study’s statistical analysis.
“But it was quite stunning to document this large an effect so quickly.”
It was also stunning to witness what happened next.
The Montana State Legislature, under pressure from the Montana Tavern Association and tobacco lobbyists, rescinded the ban in December.
The result: heart-attack rates bounced back up almost as quickly as they dropped.
The bottom line of Helena’s plummeting, then soaring, heart attack rate is painfully obvious: secondhand smoke kills. Only 30 minutes of exposure to it causes platelets in the bloodstream to become stickier. When that happens, blood clots form more easily, which can block arteries and cause heart attacks.
So if that slate article has evidence, let us see the cites.