Engineering controls

Following the hierarchy is intended to lead to the implementation of inherently safer systems, ones where the risk of illness or injury has been substantially reduced.

They also ideally do not interfere with productivity and ease of processing for the worker, because otherwise the operator may be motivated to circumvent the controls.

Engineering control approaches are often oriented towards reducing inhalation exposure through ventilation and isolation of the toxic material.

However, isolation can also be useful for preventing skin and eye contact as well, reducing reliance on personal protective equipment which should be the control of last resort.

[9]: 12  Examples of local exhaust systems include fume hoods, vented balance enclosures, and biosafety cabinets.

[11]: 19–24 Low-turbulence balance enclosures were initially developed for the weighing of pharmaceutical powders and are also used for nanomaterials; these provide adequate containment at lower face velocities, typically operating at 65–85 fpm.

[11]: 13 Several control verification techniques can be used to assess room airflow patterns and verify the proper operation of LEV systems.

It is considered important to confirm that an LEV system is operating as designed by regularly measuring exhaust airflows.

[9]: 50–52, 59  Standardized testing and certification procedures such as ANSI Z9.5 and ASHRAE 110 can be used, as can qualitative indicators of proper installation and functionality such as inspection of gaskets and hoses.

[9]: 59–60 [13]: 14–15 Containment refers to the physical isolation of a process or a piece of equipment to prevent the release of the hazardous material into the workplace.

One of the most common flexible isolation systems is glovebox containment, which can be used as an enclosure around small-scale powder processes, such as mixing and drying.

[11]: 24–28 Another non-ventilation control used in this industry is the continuous liner system, which allows the filling of product containers while enclosing the material in a polypropylene bag.

[13]: 9–11 [15] Antistatic devices can be used when handling particulates including nanomaterials to reduce their electrostatic charge, making them less likely to disperse or adhere to clothing.

Ergonomists and industrial hygienists aim to prevent musculoskeletal disorders and soft tissue injuries by fitting the workers to their work space.

Tools, lighting, tasks, controls, displays, and equipment as well as the employee's capabilities and limitations must all be considered to create an ergonomically appropriate workplace.

These barricades are placed near an edge where a fall hazard can occur, or to surround a weak surface (such as a skylight on a roof) that may break when stepped on.

[25] This article incorporates public domain material from websites or documents of the National Institute for Occupational Safety and Health.

An inverted triangle consisting of five colored horizontal levels, each containing one tee five hazard control methods: elimination, substitution, engineering controls, administrative controls, and personal protective equipment
Engineering controls are the third most effective member of the hierarchy of hazard controls . They are preferred over administrative controls and personal protective equipment , but are less preferred than elimination or substitution of the hazards.
A light green metal enclosure with a partially opened glass sash at front
A fume hood is an example of an engineering control that uses local exhaust ventilation combined with an enclosure to isolate a worker from airborne gasses or particulates.
A clear plastic box on a desk with clear tubes emerging from its top
Vented balance enclosures used in the pharmaceutical industry can be used for nanomaterials, with the advantages of smaller size and lower turbulence.
A person in white lab gear sits in front of a rigid transparent enclosure.
Biosafety cabinets , although designed to contain bioaerosols , can also be used to contain nanomaterials.
A rigid white enclosure with a transparent window and two black invrted gloves emerging from its front
Gloveboxes are completely enclosed, but are more difficult to use than fume hoods, and may leak if used under positive pressure .
A white mat on a floor extesively soiled with soot-colored footprints
A sticky mat in a nanomaterials production facility. Ideally, other engineering controls should lessen the amount of dust collecting on the floor and being tracked onto the sticky mat, unlike this example. [ 13 ]