A policy is a deliberate system of principles to guide decisions and achieve rational outcomes. A policy is a statement of intent, and is implemented as a procedure or protocol. Policies are generally adopted by a governance body within an organization. Policies can assist in both subjective and objective decision making. Policies to assist in subjective decision making usually assist senior management with decisions that must be based on the relative merits of a number of factors, and as a result are often hard to test objectively, e.g. work-life balance policy. In contrast policies to assist in objective decision making are usually operational in nature and can be objectively tested, e.g. password policy.
In the marine environment human activities and other factors can result in algal blooms and habitat destruction, which may affect people's health and local communities. A common method for assessing the status of water quality is by measuring its optical properties to determine sewage impact, dissolved organic matter, sediment loads or biological activity.