Chimney cleaning

Polynuclear aromatic hydrocarbons (from coke, coal tar. Steelmaking, rooting, chimney cleaning Skin, scrotum, bronchus... 

Fig. 9.1. Rain falls when the water droplets in clouds turn to ice. This con only happen if the clouds are below 0°C to begin with. If the droplets are clean, ice can form only in the unlikely event that the clouds cool down to the homogeneous nucleation temperature of -40°C. When dust particles are present they can catalyse nucleation at temperatures quite close to 0°C. This is why there is often heavy rainfall downwind of factory chimneys.

Cleaning solutions Tobacco smoke Air-conditioning systems Water treatment Humidifiers Disinfectants Exhaled breath Vehicle exhausts Smoking chimneys Portable heaters Tobacco smoke Gas cookers Gas and oil heaters... 

The hazards of chemicals are commonly detected in the workplace first, because exposure levels there are higher than in the general environment. In addition, the exposed population is well known, which allows early detection of the association between deleterious health effects and the exposure. The toxic effects of some chemicals, such as mercury compounds and soot, have been known already for centuries. Already at the end of the eighteenth century, small boys who were employed to climb up the inside of chimneys to clean them suffered from a cancer of the scrotum due to exposure to soot. This was the first occupational cancer ever identified. In the viscose industry, exposure to carbon disulfide was already known to cause psychoses among exposed workers during the nineteenth century. As late as the 1970s, vinyl chloride was found to induce angiosarcoma of the liver, a tumor that was practically unknown in ocher instances. ... 

The function of a chimney is to discharge in a manner to give adequate dispersal to the products of combustion in accordance with the third edition of the 1956 Clean Air Act Memorandum on Chimney Heights. The scope of the memorandum is as follows ... 

The methods of calculating proposed chimney height are clearly laid out in the Clean Air Act Memorandum, and will be based on ... 

Chimney height calculations Third Edition of the 1956 Clean Air Act Memorandum 45/818... 

Section 1 of the Act prohibits dark smoke from trade premises (the 1956 Act only controlled smoke from chimneys). Bonfires are thus now included. Section 2 controls the rate of grit and dust emission from furnaces and the Minister may make Regulations. These are known as the Clean Air (Emission of Grit and Dust from Furnaces) Regulations 1971 and the Clean Air (Emission of Grit and Dust from Furnaces) (Scotland) Regulations 1971. 

The Memorandum covers furnaces with a gross heat input in the range of 0.15-150MW. (The 1968 Clean Air Act, Section 6, requires chimney height approvals for furnaces for burning fuel at a rate greater than 1.25 million BTUs per hour. This is equivalent to 0.375 MW.)... 

The back doors are opened, and all residuals from front-end cleaning are removed. Any additional rear-end cleaning is carried out. The deposit box at the base of the chimney flue is checked, and all flue soot is vacuumed away. 

With the public dazzled by color and companies desperate to survive, factors such as clean air, pure water, and workers safety paled in importance. In a hasty pencil sketch of his family factory in England, Perkin drew one- or two-story buildings with tall brick chimneys and smoke blowing merrily out their tops. Water for the Perkins factory came from an artesian well, and waste was, no doubt, dumped in the handy canal. 

Further problems could include damaged or deteriorating flue liners, soot buildup, debris clogging the passageway, and animals or nesting birds could also obstruct the chimney. Oil flues need to be cleaned and inspected annually because deposits of soot may build up on the interior walls of the chimney. Tab. 5.7 gives an overview of possible harmful failures of indoor combustion systems. 

These are similar to nephelometers, except that they measure the attenuation of a light beam due to the combined effects of absorption and scattering by the sample. The instrument consists of a light source, a collimator and a photo-detector. The most common application is the measurement of smoke density in chimney stacks. In this case the optical surfaces exposed to the smoke are kept clean by flows of clean air. The density of the smoke is expressed in terms of per cent opacity, per cent transmittance or optical density, where ... 

An important aspect of the unit that sometimes is overlooked is the means of venting the chamber to atmosphere at the end of each cycle. So that the metallized articles are not disturbed, air must be re-admitted at a controlled rate, and it must be dry and clean. An air intake located close to a chimney or exhaust outlet from other processes is not likely to be a suitable source. 

Benzo[a]pyrene in soot was the culprit for a large number of skin cancers in young boys who cleaned chimneys in the 1700s. The body transforms this compound to 4,5-benzo[a]pyrene oxide, a reactive epoxide that forms a covalent bond with DNA. 

Inspect home heating systems chimneys and flues must be inspected and cleaned by a qualified technician every year. Keep chimneys clear of bird and squirrel nests, leaves, and residue to ensure proper ventilation. 

These gases evolve from the burning of sulfur-containing fuels from cars and factory chimneys to cause air pollution. On our planet, life can only be possible with clean air. Consequently, we should consider to decrease air pollution. 

The colorless carbon monoxide (CO) is everywhere. Wherever there is combustion there is CO it is the predominant product above 800°C. The concentration of CO might vary from 0.1 ppm in clean atmosphere to 5,000 ppm in the proximity of domestic wood fire chimneys (Fawcett et al, 1992) and is present in significant quantities in cigarette smoke (Hartridge, 1920 Hoffman et al, 2001). The atmospheric lifetime of CO is 1 to 2 months, which allows its intercontinental transport (Akimoto, 2003). 

In England in 1775, Dr. Percivall Pott wrote a paper on the high incidence of scrotal cancer in chimney sweeps who were typically boys small enough to fit inside chimneys and clean out the soot. Pott suggested that chimney soot contained carcinogens that could cause the growth of the warts seen in scrotal cancer. Over a 150 years later, chimney soot was found to contain hydrocarbons capable of mutating DNA. 

The amount of emission of radioactive isotopes into the atmosphere through the power plant chimney depends mainly on the efficiency of electrostatic precipitators or other devices used for the cleaning of flue gases. There are two types of coal burning power plants in operation in the world ... 

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