The Federal Emergency Management Agency (FEMA) issued a bulletin Monday announcing that it will grant an additional extension to Superstorm Sandy victims for the “proof of loss” filing deadline for their flood insurance claims. Under the National Flood Insurance Program (NFIP), claimants must file a proof of loss form, a statement on the amount that policyholders are claiming under their policies.In November 2012, FEMA extended the 60-day timeframe for filing Sandy-related proof of loss documents to Oct. 29, 2013, one year from the date Sandy struck the East Coast.