(Reuters) - The administration of President-elect Joe Biden is likely to hit the ground running with a flurry of executive orders and rules touching on employment issues, starting with an emergency workplace safety standard addressing the COVID-19 pandemic, lawyers and worker advocates said.

Biden, a Democrat, may face a recalcitrant Republican-led Senate that will stymie his chances of passing the kind of progressive labor legislation he championed during the campaign or approving cabinet secretaries who can carry out changes once he takes office in January.

But, Biden can act unilaterally in the earliest days of his presidency to require federal contractors to raise wages and ditch mandatory arbitration agreements, and to rescind President Donald Trump's executive orders that barred certain kinds of diversity training, limited civil-service protections for federal employees, and expanded legal exemptions for religious employers.

Several experts said they expect Biden's first priority to be the Occupational Safety and Health Administration, which under Trump has resisted calls to issue safety rules during the pandemic and instead has issued non-binding, industry-specific guidance.

Echoing many unions and advocacy groups, Biden at an April town hall meeting criticized what he said was OSHA's failure to protect essential workers by adopting specific rules employers must follow.

Biden is likely to prioritize filling key positions at OSHA to craft a standard and immediately ramp up enforcement, according to Judith Conti, government affairs director at the left-leaning National Employment Law Project.

"OSHA has been slow walking or ignoring and dismissing complaints of unsafe workplaces and retaliation for complaining," Conti said, "so (Biden) will want to get moving right away."

OSHA last week said it had received more than 9,000 complaints related to the pandemic and had issued $2.5 million in fines in about 180 cases.

The Biden administration is also expected to immediately get to work withdrawing executive orders issued by Trump, and likely resurrecting orders that had been issued by former President Barack Obama but were rescinded by Trump, such as a requirement that companies disclose alleged violations of federal employment laws when bidding for federal contracts.

Several of the two dozen people on a labor-focused transition team unveiled by Biden's campaign this week worked in the Obama administration. They include Chris Lu and Seth Harris, who were top officials at the Department of Labor, former Equal Employment Opportunity Commission member Jenny Yang, and Jennifer Abruzzo, who was acting general counsel at the National Labor Relations Board.

Many of the moves Biden can make on his own will be directed at federal contractors, who collectively employ one-quarter of the private-sector workforce.

"He's going to change the rules to give contracts to companies that raise their minimum wage (and) are friendly to collective bargaining, and to incentivize union organizing," said Myrna Maysonet, a partner at Greenspoon Marder in Florida who represents employers.

Trump has not conceded the election, and is pursuing legal action aimed at forcing recounts in several key states. Control of the Senate will hinge on the results of two January runoff elections in Georgia. If Democrats win both of those contests, the Senate would be split 50-50 with Vice President-elect Kamala Harris representing the tie-breaking vote.

But with a Republican controlled-Senate, it could take months or years to install cabinet secretaries and undo many of the controversial employment-related regulations adopted during the Trump administration, such as DOL rules involving the standard for determining when companies are "joint employers" of franchise and contract workers and the proper classification of workers as independent contractors or employees.

Down the road, Biden's appointees could also roll back employer-friendly changes the EEOC made to its process of attempting to settle discrimination claims before suing and revive an Obama-era EEOC rule requiring larger employers to report detailed pay data broken down by sex and race.