Time of day, time of year and weather conditions strongly effect infrared exposure conditions. These numbers are valid for April through September, and from 10 am through 2 pm in clear bright sun conditions. Other conditions will require an increase in exposure. Open shade on a bright sun day may require opening up one additional stop or halving the effective film speed listed here. Due to the more consistent infrared output of tungsten lighting results should also be more consistent than for daylight exposure.
Testing is still a good idea for critical work.
Infrared output of tungsten may vary with increased bulb usage. Exposure times are in seconds. The following exposure speed data is from Eastman Kodak data sheets. Exposure times are in seconds. The same meter setting of 50 will apply in this case.