Ojos del Salado Gear and Clothing List: Extreme Clothing Guide (-25 °C)

Climbing Ojos del Salado Volcano (6,893 m) requires technical clothing that can handle extreme temperatures of -20 °C to -30 °C and winds above 60 km/h on the Puna de Atacama. The mandatory gear list includes a 4-layer thermal system, rigid high-altitude double boots (-30 °C), an 800+ Cuin down jacket, extreme-cold mittens, a sleeping bag with a -25 °C comfort rating and a high-insulation sleeping pad (R-value > 5.5), plus climbing gear for the final chimney (harness, helmet, lanyard, Jumar ascender and crampons).

At Vulcano Expediciones, after 27 years organizing expeditions to the Roof of Chile, we have seen in the field that extreme cold combined with the dry wind of the Puna freezes unsuitable gear in minutes. A mistake in choosing boots or a poor-quality sleeping bag usually ends in severe frostbite or an early abandonment of the summit attempt.

Technical Checklist of Mandatory Gear and Clothing

Here is the technical summary of the essential gear required for Ojos del Salado, sorted by category and field specification:

Vulcano Insider Knowledge: On our expeditions we see that the most common mistake is trusting simple one-piece leather trekking boots. At 4:00 AM at Refugio Tejos, with an air temperature of -22 °C and gusts of 40 km/h, the lack of a thermal inner boot causes a fast loss of feeling in the toes that forces an immediate turnaround.

The Layering System for the Puna de Atacama

In the Atacama mountains the daily temperature swing is drastic: it goes from 18 °C in direct midday sun at Laguna Verde to -25 °C in the early morning on the summit section. The key to staying warm is regulating moisture and trapping warm air with combinable layers:

[Layer 1: Merino Base] ──> [Layer 2: Fleece] ──> [Layer 3: Gore-Tex Hardshell] ──> [Layer 4: 800+ Cuin Down Jacket]
 (Sweat management)        (Heat retention)      (Windproof barrier)               (Summit insulation -25°C)

1. First Layer (Base Layer)

• Material: Heavyweight merino wool (200-260 g/m²) or quick-drying technical polypropylene.
• Recommended quantity: 2 tops and 2 bottoms. Merino wool is the best option on long expeditions because it doesn't hold odors and keeps its insulating properties even if it absorbs residual moisture.

2. Second Layer (Mid Layer)

• Fleece Pullover / Jacket: Polartec Powerstretch or grid-structure fleece.
• Thin Down or Synthetic Jacket (Primaloft / 600-700 Cuin down): Ideal as a mid-weight layer on acclimatization climbs of Volcán San Francisco or Cerro Barrancas Blancas.

3. Third Layer (Shell Layer)

• Hardshell Jacket: 3-layer waterproof membrane and 100% windproof (Gore-Tex Pro, Event or Dermizax). It rarely rains in Atacama, but the constant wind strips body heat by convection within minutes.
• High-Altitude Windproof Pants: With full-length side zips so you can put them on quickly while wearing the double boots.

4. Fourth Layer (Extreme Thermal Layer)

• Expedition Down Jacket: 800 to 900 Cuin goose down fill with raised baffle construction to avoid cold spots at the seams. It must have an adjustable insulated hood that fits over a helmet.
• Down / Synthetic Overpants: Required on summit day if you are sensitive to the early-morning cold on the icy scree toward Tejos.

Extreme Footwear: Double Boots Are Mandatory

Footwear is the most sensitive technical item of the expedition. At 6,893 meters on Ojos del Salado, the lower atmospheric pressure reduces peripheral blood circulation, raising the risk of frostbite in feet and hands.

Why Are Double Boots Non-Negotiable?

Double boots (models like La Sportiva Baruntse, G2 SM, Scarpa Phantom 6000 or Mammut Nordwand) have two independent structures:

1. Inner Boot (Liner): High-density heat-moldable foam that keeps your feet warm and dry. At night you take it into the sleeping bag to dry out accumulated moisture.
2. Outer Shell (Outer Boot): High-strength synthetic or polyamide material with an integrated waterproof gaiter that stops the icy wind and direct contact with rock-hard snow.

Vulcano Warning: Simple rigid one-piece leather boots do NOT provide enough thermal insulation for continuous, slow-paced walking on the scree between Refugio Tejos (5,837 m) and the crater (6,750 m).

Overnight Gear and Thermal Insulation

Proper rest at 5,200 m (Campamento Atacama) and 5,837 m (Refugio Tejos) determines the energy you have for summit day.

High-Altitude Sleeping Bag

We require a bag with a comfort temperature range between -20 °C and -25 °C.

• Fill: Minimum 1,000 to 1,200 grams of high-quality down (800+ Cuin).
• Treatment: Hydrophobic down to resist overnight condensation inside tents or domes.

You can check the exact temperature and insulation requirements for your gear with our Sleeping Bag and R-Value Calculator.

Double Insulating Sleeping Pad System

The cold at night doesn't only come from the air, it is also transferred by conduction from the frozen ground:

1. Closed-Cell Foam Pad (EVA / Z-Lite): Placed directly on the ground to cushion you and prevent punctures from sharp volcanic rocks.
2. Insulated Inflatable Pad (Therm-a-Rest NeoAir XTherm or similar): With internal reflective layers and an R-value above 5.0. Combining both pads guarantees a total R-value > 6.0.

Protection for Extremities, Eyes and Electronics

Hands

• Merino wool or synthetic liner gloves: They let you handle carabiners and crampons without touching the freezing metal directly.
• Thermal five-finger gloves (leather/softshell): For acclimatization days at mid elevations.
• Expedition Down Mittens (Mitts): Mandatory for summit day. Keeping your fingers together inside the mitten creates a thermal microclimate that is essential to prevent frostbite when holding poles or pulling on ropes.

Head and Face

• Thermal wool/fleece hat: Fully covering the ears.
• Merino or Windstopper balaclava: Essential protection against icy blizzards.
• Sun hat with neck flap: The desert sun at 4,000 m burns unprotected skin within a few hours.

Eyes (Extreme UV Protection)

• Category 4 Glacier Glasses: With leather or plastic side shields. At 6,000 meters in Atacama, UV radiation is 80% more intense than at sea level. Conventional Category 3 glasses let in side radiation that causes photochemical keratitis, or snow blindness.
• Glacier Goggles: Clear lenses or category 3 with anti-fog treatment. Needed if gusts of volcanic dust or whiteout wind come up.

Headlamps and Electronics in Extreme Cold

• High-Output Headlamp (300+ Lumens): Check the best headlamps for mountaineering; it should run on lithium batteries or have a battery pack with an extension cable so you can keep the battery pack inside your jacket. Conventional alkaline batteries lose their charge in under 30 minutes at -20 °C.

Technical Gear for the Final Chimney and the Ridge

Getting through the vertical rock section of the final chimney of Ojos del Salado (6,860 m) means carrying the following personal climbing gear in your pack:

1. Certified Mountaineering Helmet (EN 12492): Essential because of the risk of rocks dislodged by other climbers.
2. Mountaineering / Ski-Touring Harness: A lightweight model with adjustable buckles that fit over the bulk of the summit-day jacket and overpants.
3. Double Lanyard: With 2 self-locking safety carabiners for safe progress on fixed ropes.
4. Mechanical Ascender (Jumar / Tibloc): With a wide grip for pulling on the fixed rope while wearing thick mittens.
5. Descender (Figure-eight or ATC with a screw-gate carabiner): For a safe rappel on the descent.
6. 12-Point Crampons (Semi-automatic or Automatic): Fitted and tested on the double boots before the expedition.
7. Technical Mountaineering Ice Axe (50-65 cm): With a steel head to support you on hard snow and on the step leading to the crack.
8. Telescopic Poles: With wide snow baskets for sections of loose scree.

Hydration, Food and High-Altitude Cooking

The dry air of the Puna causes accelerated dehydration through breathing. You need to drink between 4 and 5 liters of fluid per person per day.

• Wide-Mouth Nalgene Bottles (1 Liter): With neoprene insulating covers. Hydration bladders with a hose (Camelbak) freeze within the first 20 minutes of walking.
• Stainless Steel Thermos (1 Liter): To carry hot liquid (sweet tea or broth) on the summit-day early start.
• Fuel and Stoves: Above 5,000 m conventional gas canisters lose pressure. We use winter propane/isobutane blends or white gas stoves.

To calculate the daily fuel consumption needed to melt snow at Refugio Tejos, see our Snow Melting, Water and Fuel Calculator. In severe icy gusts on the ridge, check the chill conditions with the Summit Window and Wind Chill Calculator.

Guided Expeditions and Acclimatization in Atacama

Having the right gear is half of success. The other half is following a progressive acclimatization program (see our 14-day acclimatization itinerary) that prepares your physiology before taking on Ojos del Salado.

At Vulcano Expediciones we test this clothing on our guided expedition to Ojos del Salado Volcano (6,893 m), as well as on acclimatization climbs of Nevado San Francisco (6,018 m), Cerro Barrancas Blancas (6,119 m) and more technically demanding summits such as Nevado Tres Cruces Norte (6,030 m), Nevado Tres Cruces Central (6,629 m), Nevado Tres Cruces Sur (6,749 m), Incahuasi Volcano (6,621 m) and Walter Penck Volcano (6,658 m). To understand the access roads and the geography of the area, you can read our Seismiles Route Guide.

Frequently Asked Questions About Ojos del Salado Gear

Can I use conventional trekking boots with strap-on crampons?

No. Conventional trekking boots lack the thermal insulation needed to withstand -25 °C, and their flexible sole doesn't give the rigidity crampons require, causing the crampon to come off and a very high risk of frostbite.

Why are mittens better than five-finger gloves on the summit?

At -25 °C and with 50 km/h winds, the separation of the fingers in five-finger gloves speeds up heat loss by convection and conduction. In down mittens, having the fingers close together keeps the hand warm, preventing frostbite on the final push.

Do I have to buy all the gear, or can I rent it?

In cities like Santiago or Copiapó you can rent (here is how gear rental works in Copiapó) high-cost items such as double boots, an expedition down jacket and a -25 °C comfort sleeping bag. At Vulcano Expediciones we check each climber's gear in detail before heading out to the Puna de Atacama.

Complete Planning for Your Expedition

Besides having proven technical clothing, remember to arrange the DIFROL and CONAF permits step by step in time and to organize the 4x4 logistics and huts on the Puna.

To assess weather conditions you can check the report on the best time to climb Ojos del Salado: weather and wind, complement your preparation with a physical training plan and review the real cost breakdown. If you are still deciding on the format or comparing destinations, we invite you to read the guide on unguided vs. guided expedition or the comparisons Ojos del Salado vs. Aconcagua and Ojos del Salado vs. Incahuasi Volcano.