Ammonia is one of the most widely produced and utilized chemicals in the U.S., and while numerous lab studies have been undertaken, there is no consensus on the odor threshold. In contrast to controlled lab conditions used to determine odor thresholds, the field conditions following unintentional chemical releases are uncontrolled and highly variable due to many factors. A critical component in managing the response to these chemical spills involves understanding how lab data could be applied to uncontrolled field conditions in and around the affected community. It was postulated that analysis of field data collected following accidental releases of ammonia might augment and verify data collected in lab experiments. The widespread transport and use of ammonia has resulted in a number of unintentional releases of ammonia into the environment as a result of train derailments, tanker spills, and plant accidents. In the field studies reported here, air monitoring data were collected following a variety of accidental ammonia releases. Of 6539 readings between 0 and 1 ppm, odor was detected only in 208 samples (3.2%). Of 65 readings between 1.1 and 1.5 ppm, odor was detected in 51 samples (78.5%). These data are consistent with an ammonia odor threshold within a concentration range of 1.1–1.5 ppm. This level is consistent with the recently published odor threshold data for ammonia, but is significantly lower than frequently cited historical data. Furthermore, a review of the ammonia literature demonstrates that the ammonia odor threshold is significantly lower than levels that produce eye, nose, or throat irritation.
The last 3 lines give the clue. If ammonias smell can be detected at 1.5 ppm it should in most cases give plenty of warning. No one would hang around for half an hour breathing 2,000 ppm.
Anhydrous ammonia is not dangerous when handled properly, but if not handled carefully it can be extremely dangerous.
Absolutely correct Megan . However she same can be said of gasoline and LNG. Each one has their individual dangers but are about on a par with each other in terms of overall risk in transportation and at the point of use. The big trouble with the hydrocarbon fuels is greenhouse gas not to mention hidden costs and dangers in their extraction , transportation and refining.
1 Health problems: An extract from an article by business commentator Ian Verrender titled
The Hidden Costs of Coal sums it up.
‘But there are other costs that the president has ignored with his decision to withdraw from the Paris Accord. Most of those relate to the health of Americans.
‘According to the US Environmental Protection Authority – which has been neutered under the Trump administration – the clean power plan would prevent around 3,600 premature deaths, 1,700 heart attacks, 90,000 asthma attacks amongst children, and 300,000 missed work and school days each year.’
More on fossil fuels
The Hidden Costs of Fossil Fuels | Union of Concerned Scientists