The orange indication material in a Squirter® and DuraSquirt® DTI has an operating temperature of -60*F to +200*F. We froze them on dry ice to minus -53*F and baked them to +200*F to see that they still work. At jobsites, they worked at -40*F in Alaska, USA, Fort McMurry, Canada and Sakhalin Island, Russia, and in the deserts of the Middle East and Southern California with ambient temperatures of 110*F with the steel surface at 140*F.
Why does the bright orange indication media seem to not work when temps go below freezing?
DTIs are mini load cells that function independent of torque. They are hardened, washer-shaped devices incorporating small arch-like protrusions on the bearing surface. These protrusions are designed to compressed as the structural bolt is tensioned.
As these bumps are compressed by the bolt being tensioned, Squirter® and DuraSquirt® DTIs provide a bright orange mark. If the bolts haven’t been tensioned, they won’t display this bright orange mark no matter how much torque is applied.
When Squirter and DuraSquirt DTIs do not indicate in cold weather, they are still working. They are just indicating that the minimum required bolt tension has not yet been achieved. This is common with pneumatic wrenches as condensation within the air supply freezes, greatly reducing the torque output.