Design Guidelines for Special Forces Sleeping Bags: Addressing User Needs in South Korea

Special forces operatives need sleeping bags that keep them warm in extreme cold while staying light and compact enough to carry with heavy combat loads. Minimum temperatures on the Korean Peninsula range from −25 °C south of the Military Demarcation Line to −35 °C in the northern regions (2009–2018 data). Current sleeping bags used there have thermal ratings of only 4–5 Clo (a unit of thermal insulation), which the paper calls inadequate, and they often fail to balance warmth with weight and volume. The paper states that no design guidelines existed for the specific operational and physiological needs of the ROK Special Forces (ROK-SF) in extreme cold.

A mixed-method approach combining four components:

• Desk research: review of patents, scholarly articles, industry reports and online resources (Google Scholar, Google Patents, snowballing); eleven articles and eighteen patents selected for qualitative analysis. Size Korea data on the average height of military-age personnel were used for sizing.
• Benchmarking: hands-on evaluation of two commercially available and six military-sourced sleeping bags (thermal performance, weight, size, material durability, user features).
• Expert interviews: four experts (two camping experts, a sleeping bag expert and a backpacker who formerly served in the special forces); semi-structured on-site interviews of about three hours with around 40 questions, audio-recorded, transcribed and analyzed with Braun and Clarke's thematic analysis.
• Military personnel: twelve personnel from the Special Warfare Command were interviewed (two parts of about two hours each) and completed a 24-question paper survey. Recording was not permitted, so four researchers took notes, which were cross-checked in a two-hour workshop and analyzed thematically.

The results are proposed design guidelines, informed by the qualitative and benchmarking findings below (not tested on a prototype):

• Thermal performance: a target thermal rating of 6.5 Clo, compared with 4–5 Clo for existing military bags, achieved through hybrid insulation combining goose down and synthetic fibers. Experts preferred multi-layered insulation systems.
• Mass and volume: a maximum weight of 2.7 kg (current winter models: 3.0–4.5 kg, volumes over 4 L) and inner dimensions of 2000 mm length and 800 mm width (±30 mm) to fit Korean military personnel.
• Form: a mummy-type design for warmth retention and compactness, with a non-slip base and an adjustable hood.
• Modularity and user features: detachable components, integrated hot pack pockets, adjustable layering, zippers operable from inside, internal pockets, anti-snagging zippers and emergency escape functions. Durable, breathable materials such as ripstop nylon and Gore-Tex and reinforced stitching are recommended.
• User feedback: special forces personnel reported that current gear often fails to retain heat in sub-zero temperatures. They saw the 6.5 Clo target as a significant improvement and received the 2.7 kg target and compact dimensions well.

The paper presents comprehensive design guidelines for military sleeping bags for extreme cold on the Korean Peninsula, emphasizing thermal efficiency, lightweight construction, durability, user-centric features and adaptability. The authors expect these to improve operational readiness and comfort, with possible application in broader military and extreme outdoor settings. The stated limitations are the reliance on general Size Korea anthropometric data, which may not reflect ROK-SF personnel selected through strict physical criteria, and the limited representation of special forces personnel in the interviews. Future work should collect demographic data directly from ROK-SF Headquarters, include a larger and more diverse sample of current ROK-SF members, and field-test prototypes in simulated extreme conditions.