Hydraulic fracturing in the United States with hydraulic fracturing activity versus those without, with each well addition increasing rates of accidents by 2% and risk of fatality by .6%. Rig-Up and Rig-Down are terms used to refer to the delivery, construction, dismantling and breakdown of equipment required throughout the hydraulic fracturing process. Incidents and fatalities during rig-up/rig-down operations may result if struck or crushed by the heavy equipment involved. Hazards during Mixing and Injection Workers may be exposed to dangerous chemicals while mixing and injecting fluids used in hydraulic fracturing. Potential chemicals include, hydrochloric and hydrofluoric acid, biocides, methanol, ethylene glycol, guar gum, polysaccharides and polyacrylamides,
Gel pen some have finger grips of rubber or plastic. The size of the nib or pen tip ranges from to . Compared to other inks, gel ink has higher viscosity, which supports a higher proportion of pigments in the medium. The pigments are typically copper phthalocyanine and iron oxides, and the gel is made up of water and biopolymers, such as xanthan gum and tragacanth gum, as well as some types of polyacrylate thickeners. The pigments are opaque, and gel pens are available in several bright and pastel colours, as well as opalescent, metallic, and glittery colours which show up clearly