Good question.

Colorado State University Extension Agents have tested various foods and recipes in an electric pressure cooker at elevations between 3,000 and 10,000 feet above sea level in 2019 & 2020.

Some general guidelines for cooking at elevation can be made, but variations are inevitable, as mechanical function was found to differ from cooker to cooker, even when using the same brand, make and model for testing. 

The altitude adjustments on the chart below suggests increasing the cooking time by 5% for every 1,000 above 2,000 ft.  Testers did not always find this necessary based on the type of food cooked.  Adjustments where most often needed for dry beans, rice and bringing milk to 180° F for making yogurt.

Elevation

Increase

Cooking Time

3,000 ft.+5%

4,000 ft.+ 10%

5,000 ft.+15% (Denver Metro is 5,280-5,400 ft.)

6,000 ft.+20%

7,000 ft.+25%

8,000 ft.+30%

9,000 ft.+35%

10,000 ft.+40%

A longer cooking time might also require a slight increase in the amount of liquid needed (2-4 Tablespoons), particularly when cooking dry beans and rice.

Some foods cooked at higher elevation will also need 5-10 minutes natural release time, even if the directions call for a quick release. This extra time helps thoroughly hydrate and cook dry foods. It also helps avoid a potentially dangerous stream of liquid and foods escaping from the vent control knob.

We recommend you test any new to you recipe using the ingredients, functions and/or times listed during your first preparation of the food.  Test meat, poultry, fish and eggs with a food thermometer, to be sure they have reached the recommended internal end temperature for safety.