Installing a new wood floor is usually about aesthetics: brown or black? Glossy or matte?

Now, some Americans and businesses are grappling with another feature: formaldehyde.

Uneasy consumers have flooded state and federal safety agencies with inquiries about Lumber Liquidators, the discount flooring retailer accused in a “60 Minutes” episode of selling laminate wood with high levels of formaldehyde, a known carcinogen. Should they rip it out? Leave it in? And what are the dangers to adults, children or even pets?

Attorney General Eric T. Schneiderman of New York has now opened an inquiry into whether the company violated safety standards. Safety officials in California are also likely to investigate.

But federal regulators, armed with murky rules or none at all, have scrambled to respond, leaving consumers largely responsible for assessing the risk. Formaldehyde exposure can cause immediate health problems like respiratory and sinus effects, but the effects of long-term exposure remain unclear.

That has left many Lumber Liquidators customers concerned about what they should do.

Sol Hesney, 66, and his wife, Lynne, said they were mystified when their two dogs became sick shortly after they moved into their apartment in Fort Lee, N.J., five years ago.

“The vet was stumped. We were stumped,” said Mr. Hesney, who ultimately had both dogs euthanized.

After the news of Lumber Liquidators’ high-formaldehyde flooring broke on March 1, Mr. Hesney said he and his wife decided that they would replace their floors — they had installed the company’s Chinese-made laminate floors before moving in.

“We looked at each other and said, ‘Maybe that’s what explains this. It’s just too coincidental,’ ” he said. Since they moved in, he said, he had three serious sinus colds requiring antibiotics within a year’s time, something that had never happened to him before, and his wife had bronchitis.

But regulators, at least for now, are advocating a more tempered approach.

“We are not encouraging people to rip out their flooring right now,” said Lynn Baker, an air pollution specialist with the California Air Resources Board, which enforces the state formaldehyde rules that Lumber Liquidators is accused of breaking.

Commercial customers could also be affected, although Lumber Liquidators estimates that commercial sales make up less than 10 percent of the market for laminate flooring, a cheaper alternative to hardwood. Homeowners account for the bulk of its sales.

Laminate flooring itself is commonly used in some types of commercial spaces, experts say.

Lumber Liquidators disputes the “60 Minutes” report and says its flooring is safe. The company also said it was considering offering air testing services to reassure concerned consumers.

Installers, too, find themselves on the front lines after the report.

“The installers literally don’t want to install it,” said David Hill, president of Texas Best Flooring in Dallas. Mr. Hill, who does not work with Lumber Liquidators products, said he had received hundreds of emails and at least 15 calls a day from worried consumers.

“It’s confusion. Everybody’s confused, and everybody wants it out of their house,” Mr. Hill said. A spokesman for the Occupational Safety and Health Administration said the agency was paying close attention to the Lumber Liquidators issue, though as of Tuesday it had received no formal complaints.

But while federal rules exist for workers, no federal rules protect consumers from formaldehyde or most other airborne chemicals in their homes. And while research exists on formaldehyde’s health effects, experts have difficulty correlating levels of exposure with cancer risk since so many factors can affect the development of the disease.

“Any exposure to a carcinogen can increase your risk of cancer,” said Marilyn Howarth, a toxicologist at the University of Pennsylvania’s Perelman School of Medicine.

Mr. Baker, with the California agency, said consumers should ask two questions: How long has the flooring been installed, and have they been feeling sick?

“If the flooring has been installed more than a couple of years ago, most of it has probably already off-gassed,” he said, meaning that the chemical would probably have been released. “If it was just installed last week, that’s a different story — you definitely want to ventilate the home.”

The floorboard controversy bears a resemblance to the cases of Chinese-made drywall that released sulfur gases into thousands of homes built after the 2005 hurricane season, which resulted in metal corrosion and health complaints. But while the drywall gases were expected to be released for decades, formaldehyde emissions in flooring may not last as long.

“You’ll get a fairly large amount that off-gasses early on, and then it starts to become less over a period ranging from months to a couple of years depending on the amounts contained in the product,” Mr. Baker said.

Most new floors emit small levels of formaldehyde. But it also seeps out of adhesives used to bind furniture and other household items, affecting the quality of the air residents breathe.

To combat its harmful effects, governments around the world have limited the use of formaldehyde in household products, particularly those made of wood. In Europe, chemical emissions from composite wood products are tightly regulated, and Japanese regulators put the onus on home builders to limit formaldehyde levels over all within houses they construct.

The United States, however, trails when it comes to such regulations. California enacted rules to cap emissions from composite wood products sold in the state. As far back as 2009, the Environmental Protection Agency said it was considering adopting California’s limits nationwide, and it issued a proposed rule in 2013.

But after many delays at the request of the wood products industry, the E.P.A. has yet to complete its rule. On Tuesday, the E.P.A. said it had no plan to investigate Lumber Liquidators, citing the lack of a finished rule. The agency says it is trying to give consumers “actionable guidance” when it comes to formaldehyde from composite woods, according to Bob Axelrad, a policy adviser in the office of air and radiation.

That includes proper ventilation, when possible, and using reliable air testing methods.

David Krause, an environmental consultant at the consulting firm Geosyntec and the former state toxicologist of Florida, said ventilation helped but was not always a solution: Humidity, for example, can intensify the problem.

Testing indoor air quality is also not a simple proposition — mainly because federal standards are geared toward workplaces, not homes. There are no definitive testing levels, and people react in different ways to the chemical.

“We really don’t have anything that is enforceable,” Dr. Krause said.

Still, based on current knowledge of the Lumber Liquidators’ product, he added: “This is not a ‘Your hair’s on fire’ emergency.”

The Consumer Product Safety Commission may take a lead role in investigating Lumber Liquidators. The commission can push for a recall if it can prove direct harm to human health.

But that would involve a long regulatory inquiry. Several consumers have begun pursuing a different path: suing the company.