Curing times can be altered by a number of variables such as relative humidity and ambient temperature.
However, once the cure time has elapsed, the best method of checking your liner is by feel and sight. Checking your liner using a CCTV Inspection Camera is an important step in any relining job.
If you notice the ends are curling or if on touch the impregnated liner is still sticky, these are good indicators that you need to allow more time to complete your curing process.
Remember you can always re-inflate a Packer until the curing has set but be sure to do another check using CCTV Inspection Camera vision before removing a Packer completely.
Always refer to your Installation Manual for each type of installation method.