The House Administration Committee announced last week it would begin offering Members “combination” BlackBerry units, which feature both mobile phone and e-mail capabilities — despite the fact that the devices are not yet supported by the chamber’s emergency notification system.

In a March 22 “Dear Colleague” letter announcing availability of the new BlackBerries — sometimes referred to as “BlueBerries” because of the units’ color — House Administration officials also noted coverage for the device “is limited inside the Capitol and other House office buildings.”

“These new combination devices are not a substitute for the existing BlackBerry 957 devices provided by the House to Members,” wrote House Administration Chairman Bob Ney (R-Ohio) and ranking member John Larson (D-Conn.).

Unlike the data-only BlackBerry devices, distributed to Members in the wake of Sept. 11, 2001, which operate on a satellite-based network, the new combination devices use cellular networks to conduct information.

That difference previously prompted concerns that the combination devices could fail during a mass evacuation or similar emergency if mobile networks are overloaded by users, similar to what happened following the 2001 terrorist attacks.

In response, several cellular providers are working with House officials to determine if similar problems can be avoided in future emergencies.

“All the companies are working with CAO and House Information Resources to demonstrate to the House that their networks are capable of carrying the emergency network,” said Brian Walsh, a House Administration spokesman. He later added: “We’re basically working with them to see if they need to set aside emergency channels.”

One source familiar with the notification program said that despite testing it remains unclear how a cellular-based system would perform under the heavy usage that would likely occur in an emergency situation.

“There is no guarantee at all that that will not happen even with the new technology,” the source said, referring to the failure of the cellular system in 2001. “We have not put these in action. Until something happens you’re gaming it.”

For now, the emergency notification system will continue to work only with the text-only BlackBerries.

“Chairman Ney wanted to make these combination devices available,” at the request of Members, Walsh said, “but make sure they recognize there are some limitation at this point.”

In fact, even as Members are officially offered the units — which cost between $149 and $320 — House officials continue to counsel their colleagues against immediately purchasing a new device.

“The Committee on House Administration, working with the Chief Administrative Officer, is evaluating options to replace existing Member BlackBerry devices,” the March 23 letter states. “Therefore, Members may prefer to delay the purchase of any new device until a determination has been made regarding a replacement device.”

In the meantime, the House will continue to fund the text-only BlackBerries, as it has done since 2001.