def standard_mask(detector):
    """Return a list of standard mask commands for the given detector."""
    assert len(detector) == 1
    size_fast, size_slow = detector[0].get_pixel_size()
    exclude = []
    for f0, s0, f1, s1 in detector[0].get_mask():
        exclude.append('LIMITS EXCLUDE %s %s %s %s' % (size_fast * f0, 
            size_fast * f1, size_slow * s0, size_slow * s1))
    return exclude
