ANSI B31.3 Latest Revision

What is the fluid service?

The amount of piping radiography and the extent of testing will depend on the particular piping designation and service.

ASME B31.3 has the following piping categories, each with different inspection requirements for different fluid service categories:

Normal-ordinary process piping

Category M-Lethal fluids

High Pressure-Exceeds ASME B16.5 pressure limits - Class 2500 flanges

Severe Cyclic-Stress at a joint exceeds 80 percent of the allowable stress range and the number of thermal cycles will exceed 7,000

Category D-Benign fluid, low-pressure, moderate-temperature service

Be more specific about your fluid service !

Please define <...lethal fluid...> because:

• Water is a lethal fluid. The LD50 in humans is about 18 gallons though one may drown in a bucketful.
• Air is a lethal fluid. Compressed air impinging on the skin has been shown to induce various problems in the circulatory system, potentially leading to death.

Slack...

IMHO, the concept and definition of "lethal service" is a nightmare under the rules of ASME.

I believe that the code should define selected liquids/slurrys/gasses as "lethal" and others as "potentially lethal" depending on temperature, pressure and location.

More info here:

http://www.chemkb.com/safety/category-m-fluid-service/

and here:

http://www.eng-tips.com/viewthread.cfm?qid=198830

http://www.ast-forum.com/ast_forum_display.asp?post=8378

This is a bit off topic....

I'm not a relevant person for the topic, but it seems ASTM E 142 gives the detail for method for controlling quality of radiographic testing in a casting...