Immediate severe health effects

Immediately dangerous to life or health (IDLH)— Any condition that poses an immediate threat to life or which is likely to result in acute or immediately severe health effects. 

Immediate Severe Health Effects An acute clinical sign of serious exposure-related reactions is manifested within 72 hours of exposure. 

Severe exposure to radiation causes immediate damaging health effects and, frequently, death. At much lower levels, radiation exposure can initiate cancer, which emerges 10-20 years later. 

IDLH NIOSH Immediately dangerous to life or health—Levels may cause severe health effects that may impair a person or prevent the ability to escape from a dangerous situation. 

Sensitizer A sensitizer is defined by OSHA as "a chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical." The condition of being sensitized to a chemical is also called chemical hypersensitivity. Certain chemicals have no immediate health effect. But if you are exposed to them several times, they can make you allergic or sensitive to other chemicals. A classic example is formaldehyde (HCHO). Typical reactions to sensitizers can include skin disorders such as eczema. When working with sensitizers, always use proper protective equipment such as gloves, respirators, etc. Once you are sensitized to a particular chemical, even minute amounts will cause symptoms. Sensitization is usually a lifelong effect. 

IDLH Immediately Dangerous to Life and Health the maximum concentration of chemical contaminants, normally expressed as parts per million (ppm, mass/mass), from which one could escape within 30 minutes without a respirator, and without experiencing any escape impairing (severe eye irritation) or irreversible health effects. Set by NIOSH. Note that this term is also used to describe electrical hazards. 

One of the most important public health tasks in the immediate aftermath of a disaster is to conduct a rapid and comprehensive assessment of population health requirements. Responders should conduct a health assessment of the community as soon as possible within the first few days following the event (Connolly, 2005). This is a multifaceted process that consists of several key elements (1) data collection for assessment of needs, (2) identification of available resources that match to defined needs, (3) prevention of further adverse health effects associated with the event, (4) implementation of disease control strategies, (5) evaluation of the effectiveness of the application of these strategies, and (6) improvement in contingency planning for future disasters. 

For an exposed military population, the dose of a CWA considered to be "low-level" is the lowest dose that results in either an immediate observable adverse health effect or which causes operationally relevant performance decrements. The most sensitive marker of an observable health effect and the purported cause of early significant performance degradation is nerve agent-induced miosis. While various exposure durations can be considered in the planning of future research, a one-time exposure or continuous exposures lasting from minutes to several hours should be the primary target duration of exposure. 

The hazards may range from those with severe immediate impact, such as acute overexposure to solvent fumes, or drying of the skin from solvent exposure to very subtle health effects such as sensitizations from isocyanates. Long term, or chronic, effects such as cancer from selected solvents or pigments must also be included. 

The purpose for estabhshing the IDLH level is to determine a concentration that permits sufficient time for a person to escape safely or to seek protection without incurring serious injury or irreversible health effects. In determining IDLH levels, the ability of a person to escape or seek protection was considered together with severe eye or respiratory irritation and other deleterious effects (e.g., disorientation or lack of coordination) that could prevent a timely escape. The IDLH level is the concentration at which the dosage received during a 30-min exposure without physical protection would cause minimal adverse health effects. However, the 30-min period is not meant to imply that people should stay in that contaminated environment any longer than necessary. In fact, every effort should be made to evacuate the locale immediately. 

Severe immediate effects (functional decrement, may require medical attention) and/or severe transient effects, and/or probable concern for pernianent/chronic health effects. 

IDLHs. The National Institute for Occupational Safety and Health (NIOSH) publishes Immediately Dangerous to Life and Health (IDLH) concentrations to be used as acute toxicity measures for common industrial gases. An IDLH exposure condition is defined as a condition that poses a threat of exposure to airborne contaminants when that exposure is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from such an environment (NIOSH, 1994). IDLH values also take into consideration acute toxic reactions, such as severe eye irritation, that could prevent escape. The IDLH is considered a maximum concentration above which only a highly reliable breathing apparatus providing maximum worker protection is permitted. If IDLH values are exceeded, all unprotected workers must leave the area immediately. 

Health hazards associated with solvents include exposure by inhalation of a solvent, which may cause bronchial irritation, dizziness, central nervous system depression, nausea, headache, coma, or death. Prolonged exposure to excessive concentrations of solvent vapors may cause liver or kidney damage. Skin contact with solvents may lead to defatting, drying, and skin irritation. Ingestion of a solvent may cause severe toxicological effects. Seek medical attention immediately. 

The condition of being sensitized to a chemical is also called chemical hypersensitivity. Certain chemicals have no immediate health effect, but exposure to them several times can make you allergic or sensitive to other chemicals. A classic example is formaldehyde (CH O). Typical reactions to sensitizers can include skin disorders such as eczema. 

---