diff --git a/src/dysh/spectra/core.py b/src/dysh/spectra/core.py
index bd6ed2d5..a35b23cc 100644
--- a/src/dysh/spectra/core.py
+++ b/src/dysh/spectra/core.py
@@ -4,6 +4,7 @@
 
 import warnings
 from copy import deepcopy
+from functools import reduce
 
 import astropy.units as u
 import numpy as np
@@ -109,12 +110,54 @@ def find_blanks(data):
     Returns
     -------
     blanks : `~numpy.ndarray`
-        Array with indices of \blanked integrations.
+        Array with indices of blanked integrations.
     """
 
     return np.where(integration_isnan(data))
 
 
+def find_nonblank_ints(cycle1, cycle2, cycle3=None, cycle4=None):
+    """
+    Find the indices of integrations that are not blanked.
+
+    Parameters
+    ----------
+    cycle1 : `~numpy.ndarray`
+        Data for cycle 1. For example, signal with the noise diode off.
+    cycle2 : `~numpy.ndarray`
+        Data for cycle 2. For example, reference with the noise diode off.
+    cycle3 : `~numpy.ndarray`
+        Data for cycle 3. For example, signal with the noise diode on.
+        Default is `None`.
+    cycle4 : `~numpy.ndarray`
+        Data for cycle 4. For example, reference with the noise diode on.
+        Default is `None`.
+
+    Returns
+    -------
+    goodrows : `~numpy.array`
+        Indices of the non-blanked rows.
+    """
+
+    nb1 = find_non_blanks(cycle1)
+    nb2 = find_non_blanks(cycle2)
+    if cycle3 is not None:
+        nb3 = find_non_blanks(cycle3)
+    else:
+        nb3 = nb1
+    if cycle4 is not None:
+        nb4 = find_non_blanks(cycle4)
+    else:
+        nb4 = nb2
+    goodrows = reduce(np.intersect1d, (nb1, nb2, nb3, nb4))
+
+    if len(goodrows) != len(cycle1):
+        nblanks = len(cycle1) - len(goodrows)
+        logger.info(f"Ignoring {nblanks} blanked integration(s).")
+
+    return goodrows
+
+
 def exclude_to_region(exclude, refspec, fix_exclude=False):
     """Convert an exclude list to a list of ~specutuls.SpectralRegion.
 
diff --git a/src/dysh/spectra/scan.py b/src/dysh/spectra/scan.py
index a50468f7..05685afd 100644
--- a/src/dysh/spectra/scan.py
+++ b/src/dysh/spectra/scan.py
@@ -21,6 +21,7 @@
 from .core import (  # fft_shift,
     average,
     find_non_blanks,
+    find_nonblank_ints,
     mean_tsys,
     sq_weighted_avg,
     tsys_weight,
@@ -667,20 +668,15 @@ def __init__(
         self._refoffrows = sorted(list(set(self._calrows["OFF"]).intersection(set(self._scanrows))))
         self._refcalon = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refonrows]
         self._refcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refoffrows]
-        # now remove blanked integrations
-        # seems like this should be done for all Scan classes!
-        # PS: yes.
-        nb1 = find_non_blanks(self._refcalon)
-        nb2 = find_non_blanks(self._refcaloff)
-        goodrows = np.intersect1d(nb1, nb2)
-        # Tell the user about blank integration(s) that will be ignored.
-        if len(goodrows) != len(self._refcalon):
-            nblanks = len(self._refcalon) - len(goodrows)
-            print(f"Ignoring {nblanks} blanked integration(s).")
+
+        # Catch blank integrations.
+        goodrows = find_nonblank_ints(self._refcalon, self._refcaloff)
         self._refcalon = self._refcalon[goodrows]
         self._refcaloff = self._refcaloff[goodrows]
         self._refonrows = [self._refonrows[i] for i in goodrows]
         self._refoffrows = [self._refoffrows[i] for i in goodrows]
+        self._nrows = len(self._refonrows) + len(self._refoffrows)
+
         self._nchan = len(self._refcalon[0])
         self._calibrate = calibrate
         self._data = None
@@ -977,11 +973,26 @@ def __init__(
         self._sigoffrows = sorted(list(set(self._calrows["OFF"]).intersection(set(self._scanrows["ON"]))))
         self._refonrows = sorted(list(set(self._calrows["ON"]).intersection(set(self._scanrows["OFF"]))))
         self._refoffrows = sorted(list(set(self._calrows["OFF"]).intersection(set(self._scanrows["OFF"]))))
-        self._sigcalon = gbtfits.rawspectra(self._bintable_index)[self._sigonrows]
-        self._nchan = len(self._sigcalon[0])
+        self._sigcalon = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._sigonrows]
         self._sigcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._sigoffrows]
         self._refcalon = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refonrows]
         self._refcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refoffrows]
+
+        # Catch blank integrations.
+        goodrows = find_nonblank_ints(self._sigcaloff, self._refcaloff, self._sigcalon, self._refcalon)
+        self._refcalon = self._refcalon[goodrows]
+        self._refcaloff = self._refcaloff[goodrows]
+        self._refonrows = [self._refonrows[i] for i in goodrows]
+        self._refoffrows = [self._refoffrows[i] for i in goodrows]
+        self._sigcalon = self._sigcalon[goodrows]
+        self._sigcaloff = self._sigcaloff[goodrows]
+        self._sigonrows = [self._sigonrows[i] for i in goodrows]
+        self._sigoffrows = [self._sigoffrows[i] for i in goodrows]
+        # Update number of rows after removing blanks.
+        nsigrows = len(self._sigonrows) + len(self._sigoffrows)
+        self._nrows = nsigrows
+
+        self._nchan = len(self._sigcalon[0])
         self._tsys = None
         self._exposure = None
         self._calibrated = None
@@ -1232,6 +1243,21 @@ def __init__(
             self._sigcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refoffrows]
             self._refcalon = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._sigonrows]
             self._refcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._sigoffrows]
+
+        # Catch blank integrations.
+        goodrows = find_nonblank_ints(self._sigcaloff, self._refcaloff, self._sigcalon, self._refcalon)
+        self._refcalon = self._refcalon[goodrows]
+        self._refcaloff = self._refcaloff[goodrows]
+        self._refonrows = [self._refonrows[i] for i in goodrows]
+        self._refoffrows = [self._refoffrows[i] for i in goodrows]
+        self._sigcalon = self._sigcalon[goodrows]
+        self._sigcaloff = self._sigcaloff[goodrows]
+        self._sigonrows = [self._sigonrows[i] for i in goodrows]
+        self._sigoffrows = [self._sigoffrows[i] for i in goodrows]
+        # Update number of rows after removing blanks.
+        nsigrows = len(self._sigonrows) + len(self._sigoffrows)
+        self._nrows = nsigrows
+
         self._nchan = len(self._sigcalon[0])
         self._tsys = None
         self._exposure = None
@@ -1507,6 +1533,21 @@ def __init__(
         self._sigcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._sigoffrows]
         self._refcalon = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refonrows]
         self._refcaloff = gbtfits.rawspectra(self._bintable_index, setmask=apply_flags)[self._refoffrows]
+
+        # Catch blank integrations.
+        goodrows = find_nonblank_ints(self._sigcaloff, self._refcaloff, self._sigcalon, self._refcalon)
+        self._refcalon = self._refcalon[goodrows]
+        self._refcaloff = self._refcaloff[goodrows]
+        self._refonrows = [self._refonrows[i] for i in goodrows]
+        self._refoffrows = [self._refoffrows[i] for i in goodrows]
+        self._sigcalon = self._sigcalon[goodrows]
+        self._sigcaloff = self._sigcaloff[goodrows]
+        self._sigonrows = [self._sigonrows[i] for i in goodrows]
+        self._sigoffrows = [self._sigoffrows[i] for i in goodrows]
+        # Update number of rows after removing blanks.
+        nsigrows = len(self._sigonrows) + len(self._sigoffrows)
+        self._nrows = nsigrows
+
         self._nchan = len(self._sigcalon[0])
         self._tsys = None
         self._exposure = None