Answer to Question 1
Enclosures are devices that completely encompass the employee's head, much like the helmets worn by jet pilots.
Earplugs (also known as aurals) are devices that fit into the ear canal. Custom-molded earplugs are designed and molded for the individual employee. Premolded earplugs are generic in nature, are usually made of a soft rubber or plastic substance, and can be reused. Formable earplugs can be used by anyone. They are designed to be formed individually to a person's ears, used once, and then disposed.
Superaural caps fit over the external edge of the ear canal and are held in place by a headband. Earmuffs, also known as circumaurals, cover the entire ear with a cushioned cup that is attached to a headband. Earplugs and earmuffs are able to reduce noise by 20 to 30 decibels. By combining earplugs and earmuffs, an additional three to five decibels of blockage can be gained.
Answer to Question 2
HazardProtection Devices
Flying particles, chips, sand, and so onFace shield
Hot sparksFace shield
HeatReflective face shield
Molten metalFace shield
Chemical splashFace shield
Ultraviolet light and infrared heatWelding helmet or welding shield with shaded lens
Examples of different cell types in humans
Biotic interactions within and among three Aspen Parkland community types, drawn by Bird
Audiometry. The child in this photograph is undergoing a hearing test with an audiologist.
Meta-analysis of 18 studies shows that aerobic exercise causes better performance in older adults on
Types of Proteins
The two types of photoreceptors in the retina