SK-1 Protective Coverall

The SK-1 Protective Coverall

The Soldier is Wearing:
The soldier in this picture represents a typical Red Army chemical forces soldier wearing the standard issue SK-1 protective coverall, boots, gloves and the ShM-41 mask. This representation would be correct for anytime between 1941 and the late 1950's.

Sources Cited

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of the Inter-War Period

The SK-1 защитный комбинезон or protective coverall was developed in the mid-1930’s as the Red Army’s first impermeable protective suit. Early versions of the SK-1 were made of a double layered oilcloth and secured by means of laces. Red Army sources reported that it was effective against liquid blister gasses for at least three hours at 95° Fahrenheit. This suit was not effective in cold weather because the oilcloth fabric became brittle at low temperatures. Around 1941 SK-1 versions were made of a rubberized material similar to that found in the later OZK. Toggles were used in place of laces to speed the donning of the suit. This rubberized version was effective to temperatures of -40° Celsius. It is reported to be effective against liquid blister gases for 40 to 50 minutes at 95°Fahrenheit.

The SK-1 protective coverall is comprised of three major components: the coverall, a pair of overboots, and a pair of rubber gloves.

Not surprisingly, the four-kilogram coverall is the largest single part of the suit. It is issued in three sizes based on the height of the wearer. Our example states that it is a size 3 and it fits a 6’1 mannequin. It should be noted that the SK-1 coverall provides good protection against toxic substances, but is not completely airtight.

Sizes of the SK-1 Protective Coverall
Size	Soldier Height
3	Over 172 cm	Over 5’8”
2	165-172 cm	5’ 6”- 5’8”
1	Under 165 cm	Under 5’6”

Despite this, it is sufficient for protection against vapor, dust, and aerosol hazards of the period. The coverall is pale green in color.

Like the SK-1 suit itself, the knee length overboots are composed of either oilcloth or rubberized fabric. The oilcloth versions are reported to resist blister agents for approximately one hour at 95° Fahrenheit. The rubberized versions with heavy canvas soles can provide protection against blister agents for three to four hours.

Sizes of the SK-1 Protective Boots
Overboot Size	Soldiers Boot Size
3	37,38,39,40
2	41, 42
1	43+

The pair of boots weigh two kilograms. Early versions came in sizes between 41 and 46. Our later example says it is size 1, so it is possible that the system changed over the years to reflect something identical to the later OZK size chart (seen at right). The rubber gloves of the SK-1 weigh approximately 350 grams each.

SK-1 protective coveralls were used from 1936 into the early 1950’s when it was replaced by the OZK suit. The phase out did not happen at once, but gradually. The SK-1 can be found in military NBC defense manuals and posters well into the early 1960s. As they were retired from army service many were transferred to the civil defense forces where they remained into the early 1970’s.

More about the uniform...

Red Army reports infer that the SK-1 was not a general issue item for all troops, but rather restricted to chemical forces troops in particular.

It was difficult to don quickly because the one-piece ‘step into’ design. The fact that the boots had to be donned separately further complicated matters.

The suit also became quite hot if worn for a prolonged period of time. Overheating of the wearer was also a problem that Soviet publications of the era cautioned against. Red Army guidelines for wear based on local temperature are shown above. It should be noted that the top two categories also caution the commander to take precautions against heat stroke.

Temperature	Safe Operating Time
+30 C or higher (86 F or higher)	15-20 minutes
+25 to +29 C (76 to 85 F)	25-30 minutes
+20 to +24 C (67 to 75 F)	40 to 60 minutes
+15 to +19 C (59 to 66 F)	1.5 to 2 hours
+15 C or less (59 F or less)	4 - 5 hours

When compared to Western suits the SK-1 is uncomfortable, but provides very good protection against all chemical and biological agents. Their chief limitation is how rapidly they overheat the wearer and how slow they are to don. Its successor, the OZK would attempt to remedy these deficiencies.

Introduced around 1936, the SK-1 protective coverall was the first attempt to provide chemical troops protection from toxic materials. It was used by the Red Army well into the 1950’s until it was replaced by the OZK suit.⁶ The coveralls were then transferred to the Civil Defense forces where they served into the early 1970’s. To find more about the suit that succeeded the SK-1, click the link below.

This Uniform Replaced...	SK-1 Protective Coverall	This Uniform was Replaced by...
Nothing. The SK-1 was the first Red Army protective coverall suit.	SK-1 Protective Coverall	ОЗК (Общевойсковой защитный комплект)

(1) Azareev, S. I. and N. A. Balashov, боевая служба красноармейца-химика [Military Service of the Red Army Chemist], Moscow: Military Publishing NKO, 1941.

(2) Гражданская оборона [Civil Defense]. Edited by A. T. Altynina, Moscow: Military Publishing House, 1982.

(3) Jane’s NBC Protection Equipment 1988-89, Edited by Terry J Gander, Alexandria, VA: Jane’s Publishing Group, 1989.

(4) Pankov, G and B Predtechenskii, пособие санитарно-химической защите [Manual for Sanitary-Chemical Protection], Moscow: Medgiz, 1940.

(5) радиоактивные и отрабляющие вещества, бактериалые средства и защита от них [Radioactive substances, bacterial agents and protection from them], edited by B. T. Emelyanova, Moscow: Military Publishing House, 1962.

(6) Shalito, Anton, Ilya Savehenkov, Nikolay Roginskyand Kirill Tsyplenkov, Red Army Uniforms 1918-1945 in color photographs, Moscow: Windrow & Greene, 2006.

(7) TM 30-430: Handbook on U.S.S.R Military Forces, Washington D.C: War Department, 1945.

(8) Руководство по ремонту средств противохимической защиты и приборов [Repair guide for chemical protective equipment and devices], Edited by V. V. Golovanova, Moscow: Military Publishing House, 1959.