ML (Maska Ludowa - People's Mask)(possibly Maska Ludności - Population Mask) - a mask of Polish production intended for civil defense. It is derived in a straight line from the Soviet GP-4u mask. It is the successor to the civilian type gas mask
It was in use from 1969 to closely unknown date but there is info that the gas mask was prduced alongside MC-1 for a while
Filter[]
This mask was issued with two filters. A GP-4 filter and an E-014 (Not EO-14, Poles used other filter naming than Soviets). A ML issued GP-4 filter wasn't the actual GP-4 filter imported from USSR, because it has latin alphabet markings. Sometimes a mask was issued with a coffee can style adsorber (chemical filter without particular layer) but this configuration isn't as common as with GP-4 and E-014 filters.
Facepiece[]
The facepiece is made from lighter, more flexible ruber than a GP-4u, so it can make a better airtight seal. Also, because of the shape of a facepiece, it directs the air onto the lenses to defog them.
Valve assembly[]
The difference between ML and GP-4u valve assemblies is the exhale valve pattern. ML has more ventilation holes so the exhale resistance is slightly smaller in ML. Poles didn't issue the mask with the tissot tube, but the metal tube inside, around the inhale valve is still there.
Hose[]
It is noticeably longer than in Civil type mask. Most of them are covered in stocking net, but the late production ones have pure rubber without material cover. Many hoses have leaks in a screw that connects with a filter, but if the filter is screwed in, a mask is airtight again.
Straps[]
Most ML masks have strap buckles moulded into the rubber, all straps are tightened by pulling the bottom two straps. Newer models have the strap system similar to the MC-1.
Use[]
The use of the ML mask was very limited. The author did not find a single photo confirming use in civil defense exercises. SzM-41 and SzM-41M masks were used much more often.