Employees of Widener Library are concerned that a "Pardon our dust" policy during preparations for the June renovations may be causing them more than just inconvenience.

And though library officials say there is nothing to worry about, employees say concerns about silica dust--a potential carcinogen--in the air have not been adequately answered.

In the past few weeks, employees say, dust from construction crews drilling concrete, brick, and stone has filled the air.

The $52 million renovation, scheduled to begin in earnest after Commencement, will add air conditioning, a sprinkler system, a new fire detection system and two new reading rooms to the library.

Karen L. O'Brien, the Widener employees' representative to the Harvard Union of Clerical and Technical Workers (HUCTW), said the silica dust has infiltrated several Widener offices.

Silica dust, though classified a human carcinogen by the International Agency for Research on Cancer, is considered less dangerous than asbestos, so its management is not governed by strict regulations.

Jeff J. Cushman '69-'72, project manager for the Widener stacks renovations, confirmed that recent drilling may have released silica dust into the air, but said that air sampling results had confirmed these levels were not dangerous.

"We are well within regulated limits," he said.

In response to union complaints, a team from the Occupational Safety and Health Administration (OSHA) came to Widener yesterday to take another set of air samples from several offices that had been exposed to silica dust.

Though OSHA has not yet concluded whether the air is safe, O'Brien says they did advise the Widener management to better inform its employees about safety concerns.

O'Brien said that due to a lack of straightforward information from the Widener management, employees are growing increasingly concerned about library renovations.

And so HUCTW has stepped in to advocate for workers and ask for more information to be disseminated.

O'Brien said that though union representativeshave repeatedly asked library management for alarger amount of information about renovationsspecifics, many of their requests have goneunanswered.

"They contend that they are giving usinformation," she said. "But it's often after thefact and it's just not enough."

She said that the union leadership is workingwith the Harvard College Library Joint Counsel toaddress the problem.

Possible solutions include creating a Healthand Safety Committee and initiating managementtraining sessions with the Massachusetts Coalitionfor Occupational Safety and Health, O'Brien said.

"These renovations could be very safe," O'Briensaid. "We just want more cooperation andinformation from the management."

Ed Dupree, a library assistant, also said thatincreased levels of communication could allayemployee concerns.

"Management's stance has been, `Don't worryabout it, trust us,'" he said. "But the unionstance is, `We are worried about it, we don'ttrust you, and we want proof.