When do you have to apply "lethal service"?
When do you have to apply "lethal service"?
(OP)
Dear all,
ASME defines very well what to do in case of "lethal service". Unfortunately, there is no guideline under which conditions (substances, concentration, temperature etc.) the requirement of "lethal service" have to be used.
Questions:
Are there government regulation when to apply lethal service?
Is it up to engineers, to decide which equipment requires "lethal service"?
ASME defines very well what to do in case of "lethal service". Unfortunately, there is no guideline under which conditions (substances, concentration, temperature etc.) the requirement of "lethal service" have to be used.
Questions:
Are there government regulation when to apply lethal service?
Is it up to engineers, to decide which equipment requires "lethal service"?





RE: When do you have to apply "lethal service"?
At the end of the day, it's up to the company to define what they want to consider as lethal substances even though that open you up to questions later by Regulation Agencies.
RE: When do you have to apply "lethal service"?
RE: When do you have to apply "lethal service"?
G. Gordon Stewart, P.Eng.
Gas & Oil Process Engineering Consultant
http://www.ggordonstewart.com/
ggstewar@telusplanet.net
RE: When do you have to apply "lethal service"?
A lethal substance is defined by AS4343 as a very toxic substance or highly radioactive substance which, under the expected concentration and operating conditions, is capable, on leakage, of producing death or serious irreversible harm to persons from a single short-term exposure to a very small amount of the substance even when prompt restorative measures are taken, usually with an exposure limit <= 0.1 ppm by volume (or equivalent) to NOHSC:1003. Examples include phosgene, sarin, acrolein and chloropicrin…
There are other classifications used by the Australian pressure equipment codes: Very harmful (eg chlorine, H2S), Harmful (eg high temperature steam, krypton), Non-harmful.
Of course AS4343 does not preclude engineering judgement. For example, CO2 is defined as non-harmful. But if it is part of a fire suppression system fed into a confined space, then in my experience, some aspects of the system may be subjected to more stringent safety requirements.
I hope this is helpful, but be careful "cross-pollinating" codes, as the detail of the safety requirements does not always correspond exactly.
Regards,
James Wheeler