Contaminant spread

High supply air velocities or cool supply air can cause uncomfortable drafts on the worker. Nonuniform supply air velocities with high turbulence intensity may result in decreased capture efficiency, increased contaminant spread, and increased thermal discomfort. 

For a constant exhaust flow rate, an increase in supply airflow provides better operator protection or production protection, but it also increases contaminant spread and risk of draft. Any decrease in supply airflow rate will result in a reduction of the design conditions of the operator or product protection. 

Does not produce hydraulic fracturing or promote significant lateral contaminant spreading. 

Metal reclamation of sediments uses many of the same approaches as for soils, except that sediment access is often more difficult. Once removed from the bottom of a lake or river, sediments can be treated and replaced, or landfilled in a hazardous waste containment site. The actual removal of sediments involves dredging. This can pose serious problems since dredging includes the excavation of sediments from benthic anaerobic conditions to more atmospheric oxidizing conditions. This can result in increased solubilization of metals, along with increased bioavailability (see Section 10.3) and potential toxicity, and increased risk of contaminant spreading (Moore, Ficklin Johns, 1988 Jorgensen, 1989 Moore, 1994). There are ongoing discussions as to whether it is more detrimental to remove sediments, whether for treatment or removal, or simply to leave them in place. 

When water is left to stand. Pseudomonas spp. do not only survive, but increase in number. Water should not be permitted to stand on equipment (particularly in crannies and crevices), on floors, or in sinks and wash bays. Contamination spreads with water that forms films over surfaces and on the hands and clothing of personnel. Waterborne contaminants may be... 

Kemblowski, M.W., and J.-C. Wen. 1993. Contaminant spreading in stratified soils with fractal permeability distribution. Water Resour. Res. 29 419-425. 

Along with perimeter definition, additional data should be collected to evaluate the nature of contamination spread and its degree of penetration. Bulk samples of liquids, soils, and other dust should be collected and initially analyzed for PCDD/PCDF. 

In the proximity area, samples were taken along and 2 m to each side of 3, 7, and 11-m radii marked around each mine during each sampling event. Fido and the MECHEM canines routinely detected contamination up to 11 metres from the mine centres. Because of the layout of the test field (the mines were only 30 metres apart), it was impossible to determine if contamination spread past 11 metres from the mines. Results from the blind test area suggest that contamination spread more than 11 metres, but it was... 

Will the contamination spread further, or become concentrated in certain areas ... 

Very well. But we must recommend to the Srinagar system assembly that starships are prohibited from docking with you. We cannot risk the prospect of any contamination spreading. 

Seveso Italy 1974 Land contamination Spread of dioxin Offsite emergency coordination importance. Has now developed into a series of European Commission rules. 

In order to avoid contamination spreading, the air leaktightness of the rooms containing recirculating systems is controlled and safe (radiation-shielded) storage is provided. The leaktightness between the safety systems and their auxiliary systems is periodically tested. 

Provision of heating, ventilation, and air conditioning (HVAC) within the secondary containment areas, which limits contamination spread. 

Even whan fully withdrawn tha Irradiated sections of the roda will be totally within the Inner rod room. The roda pass through the Inner rod room aneloaad In alaavaa Thaaa slaavaa mlnlmlsa contamination spread. Reactor gas la pravantad from leaking Into tha room by dynamic gaa aaala between rod and alaava at tha outside wall of the Inner rod room and by static seals between tha alaava and raactor wall. 

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