After hearing “Crocs this and Crocs that” for years, I got a pair in the mail from my mom, doyenne of comfortable footwear… and I think I get it.

Pretty much clogs made out of resin, Crocs are lightweight and squishy, with ventilation holes for airing things out down there. You’ve seen them on chef Mario Batali and President Bush, who made fashion angels weep when he paired his with dark socks and shorts.

More recently, I learned that one of the brand’s biggest markets is nurses. The slip-ons are so popular that the American Nurses Association offers their members special discounts.

But some hospitals are worried that the shoes could pose health hazards. Hospitals in Pittsburgh and South Dakota are demanding that staff only wear Crocs that are closed-toed because of the risk that needles and bodily fluids could graze the skin through those vent holes.

Over in Sweden, a hospital tried to ban Crocs after linking them to three incidents in which respirators and other machines malfunctioned. The worry is that the shoes set off static electricity that can short-circuit devices.

In Ontario, a hospital association was concerned for all of the above reasons, and sent a letter to 100 hospitals urging them to ban Crocs as a precaution.

I talked to Crocs spokeswoman Shelley Forslund who said the company has found nothing to indicate that Crocs are any more dangerous than sneakers or other types of shoes worn on the hospital ward.

She said Crocs has responded to the needs of health care workers, by coming out with the "Specialist" which has a thicker metatarsal area to protect the top of the foot.

Maine hospitals don’t seem to be as alarmed over the shoes. Mercy and Maine Medical Center in Portland said they don't have any ban on the shoes. Neither does Southern Maine Medical Center in Biddeford, although spokeswoman Sue Hadiaris said the shoes are currently under review by an internal human resources group.

You might remember that not long ago, there was a similar scare about how cell phone use in hospitals could cause equipment to malfucntion. Then studies, including one from the Mayo Clinic, showed that cell phone calls don’t cause any interference.