Chapter 13 443 fluorescent. The light box can also be used to observe color shifts from styling formulations or degradation of oxidative hair color from heat style appliances. Significant development in specular gloss measurements have been accomplished and are covered in more detail in Chapter 9. Thermal protection: This is becoming an important area of research in hair styling, particularly with respect to recent advancements in thermal styling tools allowing the consumer to easily change their hair geometry from curly to straight and vice versa. Several methods have been developed to characterize thermal damage and assess the protection from styling treatments.42 Some of these methods include fiber fragmentation techniques, differential scanning calorimetry (DSC), spectrofluorimetry, FTIR image analysis, and surface techniques such as SEM and AFM. Trained panel evaluations: Tress studies are an important tool to screen formulation development, review overall performance to determine areas of formulation improvement, and compare hair performance against several controls or market benchmarks for attribute mapping. In instrumental analysis, a single attribute of the styling product is evaluated. While objective and easier to quantify statistically, the overall properties of the styling formulation are not captured. Tress testing where a wide range of attributes can be evaluated in a single test is one step closer to consumer evaluation. Hair attributes that are judged by a panel are such things as shine, stiffness, stiffness durability, flaking, manageability, and static fly- away. Ideally panelists are calibrated by using precise definitions of each hair attribute and training the panelists to score based on a series of known controls so that assessment of each attribute is more accurate. Salon testing: When instrumental and trained panel assessment are in alignment on specific attributes and the formulation has been deemed safe to test on people, then evaluation progresses to in vivo evaluation with clinical salon testing. With the intent of providing objective clinical data, salon testing is part of the evaluation process prior to consumer use studies. The benefit of salon testing is that