Final answer:
A G1 certificate holder's permissions for working on gas appliances is based on industry-specific regulations that define BTU/hr input limitations, but specific information on the certification limitations is needed to answer the student's question.
Step-by-step explanation:
The holder of a G1 certificate is permitted to work on gas appliances with varying levels of input, measured in British thermal units per hour (BTU/h). When determining which appliances can be handled by a G1 certificate holder, we can equate one BTU/hr to approximately 0.293 Watts, as mentioned in the provided study material. However, this information alone does not directly answer the student's question regarding the specific input levels a G1 certificate holder is permitted to work with. To provide an accurate response, we would need additional industry-specific regulations or guidelines that define the limitations of a G1 certificate. The information provided from the study material discusses the conversion between BTU/hr and Watts, which is essential when understanding the power output of heating appliances, but does not link to G1 certification limitations.