Code minimum is 15psi for 15 minutes with a minimum 3" gauge (assuming its for a gas line that is 2psi or less and under 200 feet). Most fitters I know, including myself, will test at 30psi for at least 24 hours.
Testing at 7kpa, even with a low pressure gauge, will NOT help you find small leaks. This is just plain bad advice. Seven kpa is only one psi, and many new residential gas installs are 2 psi (14kpa). Use at least 15 psi, with the proper gauge (3", exceeds test pressure by 15%, but not more than 300%, increments no more than 2 psi or 2% of the maximum dial reading, whichever is less). I've seen gas lines drop a pound or two and hold. You could probably hold 1 psi without using any pipe dope. Do it proper, or don't do it at all!!!