Safety Tips for Successful Spring Events Pt.2
IFAI Tent Staking Guide
Wind Speed vs. Force
The key point to comprehend is that the wind pressure increases exponentially with speed. When wind speed doubles, this increases the pressure by four. Wind speed triples, it increases the pressure by nine, and so on.
Sometimes the fabric is held in shape under light wind conditions, and it appears to be safe and stable when installed. But when the wind suddenly changes from 10 mph to 40 mph, the anchoring of the tent is suddenly required to resist 1600% extra force. (Four times the wind speed, squared = 16 times more force.)
Check the Weather Forecast and Have a Safety Plan
If you have tents outdoors, you must check the weather. Always anchor your tents considering the weather conditions and following your manufacturer’s instructions. And if the weather turns, have a pre-arranged plan with your customer about moving the party elsewhere.
Pay Attention to the Leeward Side of the Tent
In high wind conditions, tents can often blow up, not down. Under strong winds, they act like a wing, creating lift on the back-leeward side of the shelter that is greater than the forces on the side facing into the wind. If not anchored rightly, tent stakes risk to be pulled out from the ground, or on pole tents side poles become unstable causing the out guys to fail. So, pay attention to the leeward side if you find yourself applying extra anchoring in windy conditions.
”Tent Site Exposure”
This term indicates how exposed the tent site is to windy conditions. There are various exposure conditions which range from ‘A’ being the most protected, but now virtually unused, to ‘B’ and ‘C’ being both the most common, and finally ‘D’ that is the most exposed. Also, they are explicitly defined in the building code based on the distance of the tent location to various natural or man-made ‘structures’ in the vicinity of the tent.
Most engineered tents are designed to meet ‘C’ exposures.