Mercury - Hg
Find on this page the main information about mercury (Hg): physical characteristics, dangerousness, effects on health as well as mercury vapor detection and the appropriate respiratory protection equipment (gas mask, powered air purifying respirator, SCBA).
Mercury (Hg) properties
Mercury - CAS number 7439-97-6 - also known as quicksilver is a naturally occurring silvery liquid element. Hg is naturally present in the environment (volcanoes) but its presence is largely due to industrial activity, refining, mining and fossil combustion.
| CAS | TWA (8 hours) | STEL (15 minutes) | LEL | IP | Density / Air | Filter / SCBA |
| 7439-97-6 | 0,02 mg/m³ | - | - | 10.4 eV | 6.93 | Hg |
Mercury has been used for a long time for dental amalgams (fillings), thermometers and pressure monitors, fluorescent bulbs, antiseptics, cosmetics, cells and batteries, in gold panning or as a preservative in vaccines.
Mercury effects on health
Despite its wide range of applications, mercury is an element that has been gradually abandoned because of its toxicity. Indeed the WHO (World Health Organization) considers mercury to be one of the 10 chemicals of great concern to public health.
The dangerousness of mercury lies in the fact that its use, in particular in industrial processes, is likely to easily become mercury vapors. These vapors are recognized as extremely toxic to humans and classified as neurotoxic, cytotoxic, mutagenic, reprotoxic and carcinogenic.
Chronic exposure to mercury vapors, inhalation of low concentrations of Hg vapor over a long period, deteriorates the nervous system and causes many health effects: fatigue, fever, headache, memory impairment, tremors, renal failure. Exposure to high mercury vapor concentrations results in severe acute poisoning, which can lead to death from encephalitis and pulmonary hemorrhage.
Mercury detector
The protection of workers subject to mercury vapors inhalation requires the use of detection equipment: colorimetric reagent tubes for one-off measurements, SafeAir badges for a TWA measurements or a portable opto-electronic or ultraviolet mercury vapor detector.
Mercury respiratory protection mercury (Hg)
For short exposures to low mercury vapors concentrations a gas mask fitted with an HgP3 filter provides sufficient protection. For a longer exposure time, the presence of high mercury vapors concentrations, or during an emergency response, the use of a self-contained breathing apparatus (SCBA) or a supplied air respirator system is necessary in order to isolate the operator from the polluted ambient air.