Regulations & SafetyCâu 66 / 240
Which practice is safest when pressure-testing a system for leaks?
a.Use regulated dry nitrogen, and never use oxygen or compressed air with refrigerant present
b.Use pure oxygen for a stronger test
c.Pressurize with acetylene for faster results
d.Use the refrigerant charge itself at maximum pressure
Giải thích
Leak testing should be done with regulated dry nitrogen because it is inert and will not react, and oxygen or acetylene must never be used since they can cause a violent reaction or explosion in the presence of oil or refrigerant. Compressed air can introduce moisture and, mixed with refrigerant under heat, form combustible conditions. Always use a pressure regulator so the system is not over-pressurized.
Luyện miễn phí toàn bộ 240 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Why is it important to never mix different refrigerants in the same recovery cylinder?
- A technician is about to recover refrigerant in a mechanical room. Which safety step best protects against oxygen displacement?
- After exceeding the leak rate threshold on a 50-plus-pound appliance and repairing the leak, the owner is generally required to:
- A technician witnesses a coworker intentionally venting refrigerant to save time. Under EPA enforcement, what may EPA offer to individuals who report a violation?
- A technician charging a high-pressure R-410A system should be especially aware that, compared with R-22, R-410A operates at:
- Where should refrigerant cylinders be stored to remain safe?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với EPA Section 608 Technician Certification Exam · Quy trình kiểm tra