What Is a Chemical Hygiene Officer?

The role is a designation, not a credential. There is no Cal/OSHA license or certification called “Chemical Hygiene Officer.” The employer assigns the role to someone whose background and authority fit the job.

Who Can Serve as a CHO

The regulation does not specify a degree or a number of years of experience. What it does require is that the person has the knowledge and authority to do the work. In practice, a CHO needs three things:

• Working knowledge of lab operations. They understand the chemistry, the procedures, and the hazards of what the lab actually does. They can read an SDS (Safety Data Sheet) and understand what it means for the people using the chemical.
• Experience with the chemicals in use. They know how the materials behave, what PPE (personal protective equipment) is required, what storage compatibility looks like, and what to do when something is spilled or mishandled.
• Authority to enforce the plan. They can require employees to follow procedures, stop unsafe work, approve or deny the introduction of new chemicals, and escalate issues to management. A CHO with no authority cannot do the job, no matter how technically qualified they are.

Most CHOs at California labs are senior scientists, lab managers, or operations leads who already run the technical side of the lab. At small startups, the CHO is often the principal investigator or the head of operations. At larger sites, the role may sit with a dedicated EHS manager. Either model works as long as the person meets the three requirements above.

The CHO does not have to be a full-time safety professional. They do have to be the named, accountable individual on the plan, and they have to actually do the work the plan assigns to them.

Three Tiers of Responsibility

The Cal/OSHA Laboratory Standard builds responsibility in three tiers. The CHP names who fills each one. The CHO is the top tier, but the plan only works when all three are doing their part.

This structure matters because a Cal/OSHA inspector will ask about it. They will ask the CHO who their lab supervisors are. They will ask a lab worker whether they know who their CHO is. Gaps between the tiers (a CHO who has not been told they are the CHO, a lab worker who has never heard of the plan) are some of the most common deficiencies we find when we walk a facility.

What the CHO Is Actually Accountable For

The plan assigns the CHO a specific set of duties. The exact list varies by facility, but the recurring items are:

• Keeping the chemical inventory current, with CAS numbers and corresponding exposure limits
• Reviewing SDSs for new chemicals before they enter the lab and updating the plan when a new hazard appears that the current plan does not address
• Verifying that PPE, fume hood operation, eye wash and safety shower stations, spill kits, and fire extinguishers match what the plan requires
• Confirming that initial and refresher training under 8 CCR 5191(f) has been delivered and documented (employee names, dates, topics covered, sign-offs)
• Coordinating the medical program and identifying the local hospital or clinic for emergency notification
• Reviewing the plan at least annually and updating it when chemicals, processes, equipment, staff, or the facility itself change
• Working with the HazCom program under 8 CCR 5194 so the lab’s chemical communication and labeling are consistent across both standards

During CHP creation or revision, one of the first checks is whether the CHO named in the plan still works at the facility and knows they hold the role. A plan that names someone who has left the company creates a gap a Cal/OSHA inspector can identify immediately.

How CDMS Addresses the CHO Role in the Plan and Training

CDMS does not staff or provide ongoing support for the CHO role. The regulation makes that a designation the employer assigns to an internal person who has authority over lab operations. CDMS creates the plan that defines the role and trains the person who holds it.

That typically looks like:

• Writing the CHP so the CHO’s duties are clear and tied to the specific chemicals, procedures, and facility on site
• Delivering Chemical Hygiene Training under 8 CCR 5191(f)(3) and (4), including the topics the regulation requires (Cal/OSHA standard, exposure limits, SDS use, signs and symptoms of exposure, detection methods, physical and health hazards, plan availability, protective measures)
• Giving the internal CHO a clear annual-review checklist and change triggers to manage after delivery
• Creating a revised plan and delivering updated training when the employer commissions a new CHP scope

For labs setting up the role for the first time, the BSL-2 lab requirements checklist covers where the CHO fits into the full set of California EHS programs a new lab needs.

Who keeps the plan current? Chemical Hygiene Plan annual review and ongoing lab compliance →