Private equity firm the Riverside Co. has made another add-on to Emergency Communications Network LLC (ECN) with the acquisition of PearServe.

PearServe, which does business as Dean Alert, provides voice, text and email notification services for health care, education and corporate clients. Terms of the acquisition were not disclosed.

ECN provides time-sensitive warnings, information about natural disasters and other information to citizens employees and other people. Riverside, which is headquartered in New York and Cleveland, used the service to communicate with employees when Hurricane Sandy hit the east coast in 2012. 

The acquisition deepens ECN corporate and institutional client base.

Riverside's other add-ons to ECN include DeltAlert, which the firm bought in June 2013. 

Riverside recently closed a micro-cap fund with $350 million in commitments, which followed its largest fund, a $1.5 billion fund that closed in January. The firm's co-CEOs won Mergers & Acquisitions Mid-Market Dealmaker of the Year award for 2013