# Impact time

Impact time is duration of time that it takes for an object from start of the impact to the peak load moment. Impact time is highly affecting the amount of force generated in the dynamic load. The longer is time the less is load peak.

Roughly speaking, the impact time for different ropes with the length of 2 meters are:

- Climbing ropes (dynamic): 0.075 sec
- Rope access ropes (semi static): 0.05 sec
- Dyneema, Technora ropes (ultra static): 0.0175 sec

We recommend to take this as t in calculating force in a fall. It’s very approximate but it’s more than enough in most of the cases to evaluate the amount of load you get. If you have 4 meters then multiply it by 2. 10 meters – by 5 and so on.

Mostly time depends on elongation of the rope. The higher the elongation the longer is impact time. Below we have examples for FF1 falls.

**Result:**

**Result:**

Calculations we have on this page are good for understanding impact calculation in general. But in this calculation we don’t take into consideration following important factors which affecting the Time, here are some of them:

- Fall Factor (amount of rope absorbing the shock)
- Significant change in time of impact when the rope length is high

But what is also important is Additional factors of dynamic load.