Sandy, Neill, and others What neutron spectrum is usually used to calibrate albedo neutron TLDs? Is it always 252Cf in a 30-cm-diameter D2O sphere? Are other spectra commonly used? Thanks, mike Mike McNaughton Los Alamos National Lab. email: mcnaught at LANL.gov or mcnaughton at LANL.gov phone: 505-667-6130; page: 505-664-7733