designed. The Occupational Safety and Health Administration (OSHA) and United States Environmental Protection Agency (EPA) have written numerous design standards on the assumption that a particular technology exists whose performance can meet the regulations. A regulatory target may prudently decide its safest course to compliance is to install that technology. Design-based standards are widely applied to agricultural nonpoint sources, including BMPs on cropland. For example, there can be a mandatory establishment of riparian buffer strips between the cropland and neighboring water bodies. There are also restrictions on where and at what rates agricultural chemicals can be applied to crops. Design based standards require an effective measurement approach, like BMPs, while performance standards limit pollutant discharges to a specified amount. Performance standards or emission limits Performance standards or emission limits are types of regulations that set an objective or performance level for the regulatory target to meet. What makes these regulatory approaches unique is that they do not specify how the polluter must meet the standard. These regulations can include emission limits that specify the rate, amount, and kinds of pollutants that may be emitted from a given source over a specific period. The EPA's various effluent limitations for water pollution under the CWA are simply a few of the many environmental regulations that are nominally performance standards. Product bans and use limitations These prohibit a product or activity or limit its use. Product bans and limitations apply to NPS pollution through restrictions on things like chemicals, pesticides, and food additives. For example, farmers were banned from using the insecticide DDT in 1972 for their crops because it was found to be harmful to humans and wildlife. Marketable allowances and trading system Marketable allowances are a regulatory approach that allows companies to buy and sell pollution rights. This type of regulation uses market forces to ensure that pollution is reduced in the least costly manner to the polluter. Under a marketable allowance system, there is a presumption that permits will be traded to those companies which have the highest pollution abatement costs. These companies would then sell their allowances to other companies for whom such reductions would be more expensive. Auctions to effectively allocate resources, like public pollution control expenses, could increase competition and maximize revenues in private markets for pollution control. This mechanism could also be used to improve the efficiency and cost-effectiveness of government programs. This mechanism provides better