A.Burn-Through

B.Back Weld Test

C.Branch Welding Type

D.Butt Welding Technique

A.Vapor pressure of liquids

B.Natural gas composition

C.Combustion temperature of gases

D.Suitable electrical equipment for classified locations

A.Elevated pressures

B.High temperatures

C.All of the above

D.Chemical changes

A.External Undercutting

B.Elevated Unction

C.Erosion Undercutting

D.End User

A.Certification from welding experts

B.Test results to the equipment manufacturer

C.A letter of intent to the standard committee

D.Technical documentation to the relevant authority