HAZCOM explainedIf workers are exposed to hazardous chemicals at work, OSHA’s Hazard Communication Standard (29 CFR 1910.1200) will help you identity the hazards of those materials and how to use them safely. An employer must also teach employees about the protective measures when working with hazardous chemicals. When workers have this important information, they’ll be able to take steps to protect themselves from the negative effects caused by accidental exposure.

OSHA’s Hazard Communication Standard (HCS) requires employers and manufacturers to develop and distribute chemical information as described below:

  • Chemical manufacturers and importers must classify the hazards of the chemicals they produce or import, and prepare labels and safety data sheets to convey the hazard information to their downstream customers.
  • Employers with classified hazardous chemicals in their workplaces must have labels and safety data sheets for their exposed workers, and train workers to safely handle those chemicals.

As mentioned above, the standard requires an employer to provide information to employees about the hazardous chemicals to which they are exposed, by means of:

  1. a hazard communication program,
  2. labels and other forms of warning,
  3. safety data sheets, and
  4. information and training.

Employers who do not produce or import chemicals need only focus on those parts of this rule that deal with establishing a workplace program and communicating information to their workers.

OSHA Definitions of Chemical Hazards

Do not think that the chemicals which apply to the rule are only those in liquid, gas or particulate form. But, the standard’s definition of “chemical” is much broader than that commonly used. According to the HCS, chemicals that apply may exist in one of many forms:

Dusts – are finely divided particles. Example – wood dust.

Fumes – are even smaller particles usually formed when solid metal is heated and vaporized, and then condenses as tiny particles.

Fibers – are similar to dusts but are of an elongated shape. Examples – asbestos and fiberglass.

Mists – are liquid droplets that have been sprayed into the atmosphere.

Vapors – are gases formed when liquid evaporates.

Gases – are substances that are normally airborne at room temperature. A vapor is the gaseous phase of a substance which is a normally a liquid or solid at room temperature.

Solids – such as metal, treated wood, plastic.

Liquids – the most common form in the workplace.

Chemical Effects

The effects chemicals have on the various organs of the human body depend on several important factors:

  1. The form of the chemical: Is the chemical a solid, liquid, or gas?
  2. The route of entry, or how the chemical contacts the body: is it ingested, inhaled, absorbed or injected?
  3. The dose, or amount, the body receives: How much chemical makes its way into the body?
  4. The toxicity: How poisonous is the chemical?

Routes of Entry

Another important task when assessing the workplace for chemical hazards is to determine the route(s) of entry the chemicals may take. If we know the route(s) of entry, we can then determine appropriate engineering, administrative, and PPE controls to eliminate or reduce the exposure. The four common routes of entry are:

  1. Ingestion: Do we eat or drink it?
  2. Inhalation: Do we breathe it in? This is the most common route of entry.
  3. Absorption: Does it pass through the skin, eyes or other membranes?
  4. Injection: Does it enter through a puncture or cut?


Below are some more important requirements manufacturers, importers and distributors must meet concerning SDS Managerment:

The manufacturer or importer must:

  • Prepare one SDS that applies to all similar mixtures where complex mixtures have similar hazards and contents (i.e. the chemical ingredients are essentially the same, but the specific composition varies from mixture to mixture).
  • Ensure that the SDS information recorded accurately reflects the scientific evidence used in making the hazard classification.
  • Add new information to the SDS within three months after becoming aware of any significant new information regarding the hazards of a chemical, or ways to protect against the hazards.
  • If the chemical is not currently being produced or imported, add any new information to the material SDS before the chemical is introduced into the workplace again.
  • Provide an appropriate SDS with the initial shipment, with the first shipment after a SDS is updated, and as requested by the employer or distributor.
  • Retail distributors selling hazardous chemicals to employers having a commercial account must:
    1. provide a SDS to such employers upon request, and
    2. post a sign or otherwise inform them that a SDS is available.

Employer Responsibilities

SDSs may be kept at the primary workplace facility or online, as long as the employer can ensure employees have quick access to the information.

  • Employers must obtain a SDS from the chemical manufacturer or importer as soon as possible if the SDS is not provided with a shipment that has been labeled as a hazardous chemical.
  • Employers must maintain SDSs in their workplace and must ensure that they are readily accessible during each work shift to employees when they are in their work area(s).
  • Electronic access and other alternatives to maintaining paper copies of the SDS are permitted as long as no barriers to immediate employee access in each workplace are created by such options. Make sure employees know how to quickly access SDS information that is stored on computers or online.
  • Where employees must travel between workplaces during a workshift, i.e., their work is carried out at more than one geographical location, the SDSs may be kept at the primary workplace facility. In this situation, the employer must ensure that employees can immediately obtain the required information in an emergency.
  • Employees who work at more than one site during the work shift must be able to obtain SDS information immediately (within seconds) in an emergency.
  • SDSs may be kept at the primary workplace facility, as long as the employer has a representative available at all times to ensure ready access (within a few minutes) to this information. This is the only situation in which an employer is allowed to transmit hazard information via voice communication. The employer must address in the written hazard communication plan how SDS information will be conveyed to remote worksites.
  • SDSs may be kept in any form, including operating procedures, and may be designed to cover groups of hazardous chemicals in a work area where it may be more appropriate to address the hazards of a process rather than individual hazardous chemicals.