  Multiwire and microstrip porous detectors have been developed and
investigated for DC operation. The multiwire porous detector consists of anode
wires, an Al cathode and a gap between them filled with porous CsI. The
microstrip porous detector consists of an insulating plate covered with
metallic strips, micromesh cathode and a gap between them filled with porous
CsI. For some time after being manufactured, these detectors' performances are
non-stable and they have poor spatial resolution. However, after being kept in
vacuum for a certain time, they spontaneously acquire stability and spatial
resolution better than 100$\mu$m and have detection efficiencies of 100% and
70% for heavily ionizing $\alpha$-particles and 5.9 keV X-rays respectively.
The MWPDD performs stably at an intensity of heavily ionizing $\alpha$
-particles of 711cm$^{-2}$s$^{-1}$.
