Factors to Assess

Hazard Identification Factors to Assess, Questions to Consider, and Control Tips

There are a number of individual factors to consider when identifying hazards. The most common hazards encountered in research activities can be classified into three groups: agents, conditions and activities. The following factors are not representative of all hazards, but many of these can get you started in identifying hazards in your laboratory:

  • Materials
  • Equipment
  • Facility and Conditions
  • Human Factors
  • Personal Protective Equipment
  • Regulatory Concerns


Gas is a widely used material in the laboratory and has a variety of potential hazards associated with it. For this reason, it's used as an example to represent materials in general.  

Gas under pressure and subject to sudden release is highly flammable and potentially explosive. Flammability and explosion may be increased by presence of oxidizers. Characteristics of specific gas must be considered.

Questions to ask:

  • Is gas a mixture and concentration appropriate for use?
  • Has the cylinder been maintained and stored as required by National Fire Protection Association code and manufacturer’s recommendations?
  • Has a safe amount been acquired (minimum amount required for experiment)?  


  • Reduce: Use the smallest amount of gas required and use a nonflammable mixture, if possible.
  • Substitute: Use a less hazardous gas (or process), if possible. The use of lecture-size or small volume cylinders enables storage in a fume hood.
  • Isolate: Carbon monoxide, for example must be stored in a continual flow exhaust cabinet. Nontoxic flammable gases may, under certain conditions, be used on the open bench, but are preferably used in the fume hood or gas cabinet. Order carbon monoxide with a flow restrictor in the cylinder valve where low flow rates will be used.


Gas requires storage in a gas cabinet due to toxic properties.


Make sure your equipment is in good and safe working condition. Don't forget less obvious--but potentially hazardous items--like tubing, connections, electrical outlets, and power strips.

Questions to ask:

  • Is the equipment explosion proof?
  • Can the equipment be placed in a fume hood?
  • Does use of the equipment in the fume hood block exhaust of flow? Is the equipment suitable for gas?
  • Has the equipment been maintained?
  • Is the equipment failure testable?
  • Are shutoff mechanisms available at the point-of-use?
  • Has the cylinder been secured?
  • Have proper tubing and connections been installed and tested?


  • Minimize amount of tubing and number or connections, ensuring that tubing cannot be pinched or kinked;
  • Make sure there is a shut off valve at the point-of-use and a second shutoff if the gas is remote from the equipment.
  • Have a “kill switch” available in the laboratory, if appropriate.
  • Ensure there is no potential source of ignition. Outlets and power strips must be external to the fume hood.
  • If flames are used, make sure there is a mechanism for emergency shutoff.


Reference manufacturer recommendations in your SOP. They can help laboratory workers learn the correct operation of the equipment, identify warning signs of trouble, and execute an emergency shutdown.


Processes allow you to think about each step of your experiment. When processes are outlined clearly in an SOP, the information can be useful to anyone working in the lab regardless of experience level. 

Questions to ask:

  •  Is the process under pressure or vacuum?
  •  Does the process require heating?
  •  Does the process volume increase potential for a leak, or could it result in a higher potential for injury or damage?
  •  Can the process be tested using a smaller volume of gas?


  • Write it down! Include typical processes in the SOP and explain potential associated hazards. This can be used as a reference for people who are inexperienced or new to the lab.
  • Perform a dry run of the experiment and record hazards as you identify them from start to finish. This can help you eliminate unecessary hazards or become aware of new hazards that arise.
  • Create easy-to-read checklists that everyone in the lab will understand to remind people of important steps and to encourage safe behavior, everytime.


Job Hazard Analysis and checklists help you focus your assessment on process.

Facility and Conditions

Look at your lab. Are there unnecessary materials or objects that might impede access to the equipment? Consider the impact of the lighting in the building on safety. Have you considered your emergency response?

Questions to ask:

  • Are remote shutoff mechanisms required?
  • Is an emergency power source required and effective?
  • Is a flammable gas detector or alarm required or advisable? Is a toxic gas alarm required or advisable?
  • Are lighting and other work conditions adequate? Is there a risk of static buildup due to low humidity?
  • Are emergency response measures in place (fire extinguishers, safety shower, automatic fire alarms, and fire suppression)?
  • Will emergency responders be able to locate and access the lab? Have emergency responders been advised of the experiment and materials present?


  • Perform a dry run of your experiment in the laboratory.
  • Have a fire extinguisher readily available.
  • Know how and when to use the fire extinguisher and make sure coworkers are available to assist, if necessary.


Sharing a lab? Here are some special considerations:

  • Does your experiment pose a risk to other facility operations?
  • Does the experiment location impede egress or emergency response actions for others?

Human Factors

Assessing the safety knowledge level all of the people who work in the lab (regardless of lab experience and tenure) is important to maintaining safety and key in the prevention of accidents, incidents and injury. Are your colleagues encouraged to report incidents without fear? Are laboratory workers confident in their ability to respond during an emergency and communicate with coworkers and emergency personnel?

Assessing human factors can give you a glimpse of the overall safety culture in your lab.  

The assessment of human factors shouldn't instill fear. It should be an opportunity to teach new and inexperienced lab workers while serving as a safety refresher for experienced lab workers and finding new and better ways to protect each other.

Protecting each other

Assessing human factors isn't about incompetence or blame, instead it addresses the reality that people can make mistakes, forget steps, or can be distracted due to illness, fatigue or stress.

These assessments may also reveal challenges for staff with disabilities that can lead to solutions that improve their work environment and allows them perform their tasks more safely.

Control Tips for Human Factors:

Administrative controls like training, and the distribution of clear documentation like checklists and SOPs are considered to be among the most effective control measures against human error.  

Questions to ask when assessing human factors  

  • Can the experiment be monitored at all times or automatically shut down?
  • Does the laboratory worker recognize warning signs of equipment failure, tubing failure or other factors that could lead to an accident?
  • Is the laboratory worker trained for emergency response? Is the laboratory worker working with a trained coworker?
  • Is there an internal transport procedure (cylinder secured, and so forth)?

Personal Protective Equipment

PPE is a simple defense against common accidents involving splashes and spills, but is one of the safety precautions often forgotten or ignored. Encourage your team to always wear PPE.

Control Tip: Personal Protective Equipment is a control measure. In the hierarchy of control measures, it is recommended that PPE be used after all other types of control measures have been exhausted to either completely eliminate a hazard or minimize risk.  

Questions to ask when assessing personal protective equipment

  •  Is the laboratory worker wearing flame resistant clothing and lab coat?
  •  Is the laboratory worker wearing impact resistant eye protection?
  •  Is the laboratory worker wearing proper PPE when transporting or setting up the cylinder?

Regulatory Concerns

There are several rules and regulations involved with the proper and safe operation of any laboratory. Including any issues around regulatory concerns in your Standard Operating Procedure will be helpful to anyone working in the lab get familiar with specific codes, rules and requirements. Even if you aren’t familiar with every rule in the book or code, consider some of these questions, when assessing regulatory concerns in your lab.


Questions to ask when assessing regulatory concerns

  • Is the facility and experiment in compliance with National Fire Protection Association codes (the Safety Office can obtain these) for the flammable gas to be used?
  • Have NFPA or other applicable codes (the Safety Office can obtain these) been reviewed for gas storage limitations, lab construction and emergency response requirements, compressed gas storage and use, special requirements for certain gases?

This collection of methods and tools for assessing hazards in research laboratories is based on the publication, Identifying and Evaluating Hazards in Research Laboratories [PDF]. The guide was published in 2015 by the Hazard Identification and Evaluation Task Force of the American Chemical Society’s Committee on Chemical Safety in response to a recommendation from the U.S. Chemical Safety Board.

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