When estimating the numbers of people affected, authors should bear in mind that a proportion of the population will be indoors. This will provide a degree of protection against the effects of the release as compared to being outdoors. The level of protection is related to the rate at which air and toxic material enters the building and may be measured in air changes per hour (ACH). Models exist (see Davies and Purdy, 1986) to determine the outdoor concentration required to give an indoor SLOT or SLOD DTL dose. This (usually higher) outdoor concentration effectively defines the hazard range for people inside buildings.
S -Methylmethionine is found in barley and is further created during the malting process. SMM can be subsequently converted to DMS during the malt kilning process. Lightly kilned malts such as pilsner or lager malts retain much of their SMM content while higher kilned malt such as pale ale malt has substantially more of the SMM converted to DMS in the malt. Darker kilned malts such as Munich malt have virtually no SMM content since most has been converted to DMS. Other crystal malts and roasted malts have no SMM content and often no DMS content since the kilning also drives that compound out of the malt.  
Epidemics of TSW occur in many geographic regions worldwide. The severity and timing of epidemics in a particular cropping system are the result of interactions between the thrips vector, the pathogen host plants, and the pathogen. TSWV has been found to infect plant species of natural vegetation that are found growing close to susceptible crops, and in some situations natural vegetation is an important source of viruliferous adult thrips that transmit to susceptible crops. In other situations, susceptible crops are the source of viruliferous adults invading new fields.