Metro

Subway board-er, beware!

Keep your heads down, straphangers.

Some of the most heavily trafficked subway stations in Midtown are plagued by rotting and shaky rubbing boards — the wooden strips at the very edge of the platform — even nine months after an MTA report showed that the dangerous deterioration led to several riders falling onto tracks at other stations, The Post has found.

The crumbling conditions can be found on platforms for the downtown F at 34th Street and the uptown B and D at 47-50 Streets/Rockefeller Center — which rank as the third- and 13th most-used stops in the entire system with a combined, estimated 46 million riders every year.

At those stations, the boards are so deteriorated, they’ve separated from the platform, leaving them weak and with hazardous, inch-wide gaps.

“They’re shaky! I have been standing on these boards and thought to myself, ‘Is this going to fall down with me on it?’ ” said Katerhina Martin, 38, of Queens, who uses the 34th Street station every day.

The MTA has been scrambling to repair the wooden slats — which mainly prevent damage to subway cars as they bump platform edges — after the agency’s inspector general released a scathing report on other decrepit rubbing boards in April 2009.

The report mentioned a teenage boy who fell onto Q train tracks in Brooklyn after a rubbing board gave way when he stepped on it.

“This was the third time in three years that a subway rider fell to the tracks after a defective rubbing board broke under his weight,” the report said.

All of the victims reached safety before a train arrived.

Members of the IG’s office investigated the boards now brought to light by The Post, said spokesman Michael Boxer. He said the IG routinely responds to complaints about defective rubbing boards and will release a follow-up report later this year.

“In this case, knowing this has happened at this station [34th Street], our people are out there now, and we intend to follow up with the MTA to make sure this situation revealed by the paper is corrected,” Boxer said.

Charles Seaton, a spokesman for NYC Transit, said crews just finished repairing the uptown F line platform’s rubbing boards and started work on the downtown side Saturday.

“The work will take about two to three weeks to finish,” he said.

Riders said they’ll be looking out for the hazardous conditions.

“It’s dangerous,” Will Robinson, a Bronx actor, said at the Rockefeller Center stop. “Once the train starts pulling away and someone slips, that’s it.”

tom.namako@nypost.com