Risk Assessment
Appendix : Risk Assessment
The following are tools recommended by the American Chemical Society for use in hazard assessment. Each lab should choose a method suitable to their lab.
Checklists
Checklists are a structured process for hazard/risk assessment. The most used method.
Chemical Safety Levels (CSLs):
Defined levels of hazard (1 through 4), based on a risk assessment conducted by a qualified individual:
CSL Level 1: Minimal health or physical hazard from chemicals. No concentrated acids or bases, toxics, carcinogens, or teratogens. Less than 4 liters of flammable liquids. No fume hood required and no general ventilation rate specified. Typical examples include: temperature-controlled rooms; K–12 science teaching and demonstration labs; research labs with chemical usage in prepackaged kits; or less than 500 milliliters (mL) of chemicals with the Globally Harmonized System (GHS) “danger” signal words, laser labs (below Class 2B), and microscopy rooms.
CSL Level 2: Low health or physical hazard from chemicals. Small amounts, less than 1 liter, of concentrated reagent strength acids or bases, possesses none or limited amounts of toxic or high hazard materials. Less than 40 liters of flammable liquids stored. May need a fume hood for specific activities. Typical examples include: undergraduate chemistry or biochemistry teaching and demonstration labs, and standard biomedical research labs.
CSL Level 3: Moderate chemical or physical hazard. Lab work with concentrated acids, bases, toxic, other high hazard chemicals, or cryogenic liquids. Carcinogens or reproductive toxins are handled. Corrosive, flammable, or toxic compressed gases are present in cabinets or fume hoods. Larger volumes (> 40 liters) of flammable liquids are stored in the lab. High hazards in limited quantities may be in the lab with Environmental Health and Safety (EHS) approval (for example, hydrofluoric acid, pyrophoric chemicals, or cyanides). Labs are fume hood or local exhaust intensive. Some uses of a glove box for air or water reactive chemicals. Examples include: chemistry research, pharmacology, chemical engineering, and pathology labs, as well as other chemical intensive research labs.
CSL Level 4: High chemical or physical hazard. Work with explosives or potentially explosive compounds, or frequent use of larger quantities of pyrophoric chemicals. Use of large quantities or high hazard materials with significant potential for Immediately Dangerous to Life and Health (IDLH) conditions in the event of uncontrolled release or foreseeable incident. Use of glove box for pyrophoric, or air or water reactive chemicals.
PIs and lab managers need to establish the upper limit on the quantity of high hazard materials that are used. For example, use of more than 5 grams of a pyrophoric material, or 150 mL of 2 molar t-butyllithium (in pentane) could be considered larger quantities.
Control Banding
Control Banding is a form of risk assessment and rating that prioritizes hazards based on levels of risk and exposure, which leads to appropriate control selection. Control banding divides laboratory materials and processes into “bands” based on chemical properties, processes or other logical groupings.
Failure modes and effects analysis (FMEA):
An evaluation of the means that equipment can fail or be used improperly, and the effects this failure can have on the process.
Fault tree analysis (FTA):
A graphical model that illustrates combinations of failures that will cause one specific failure of interest. It is a deductive technique that uses Boolean logic symbols to break down the causes of an event into basic equipment or human failure.
Hazard analysis:
A term used to express the complete process of hazard identification, evaluation, and control.
Hazard control:
A barrier, such as a device, measure, or limit, used to minimize the potential consequences associated with a hazard.
Hazard evaluation:
The qualitative and, whenever possible, quantitative description of the inherent properties of an agent or situation having the potential to cause adverse effects. The definition of “hazard characterization” is adapted from the World Health Organization (WHO).
Hazard identification:
The identification of the type and nature of adverse effects from an agent, operation, or equipment, which has an inherent capacity to cause in an organism, system, or (sub) population.
Hazard operability (HazOp) analysis:
A technique whereby a multidisciplinary team uses a described protocol to methodically evaluate the significance of deviations from the normal design intention.
High hazard materials (to consider for used in the application of chemical safety levels):
Can be defined in two ways: (1) materials which pose a high health hazard, and (2) those which pose a high physical hazard. High health hazard materials are substances with high acute toxicity (described below) and those which are known carcinogens as identified by the International Agency for Research on Cancer (IARC) Group 1 and Group 2A agents. Group 1 agents are carcinogenic to humans and Group 2A agents are probably carcinogenic to humans. Materials with the following GHS hazard statements are presumed to be a high physical hazard and subject to a risk assessment of its actual use:
- H201: Explosive; mass explosion hazard
- H202: Explosive, severe projection hazard
- H203: Explosive; fire, blast, or projection hazard
- H220: Extremely flammable gas
- H240: Heating may cause an explosion
- H241: Heating may cause a fire or explosion
- H242: Heating may cause a fire
- H250: Catches fire spontaneously if exposed to air
- H251: Self-heating: may catch fire
- H252: Self-heating in large quantities; may catch fire
- H260: In contact with water, releases flammable gases which may ignite spontaneously
- H270: May cause or intensify fire; oxidizer
- H271: May cause fire or explosion; strong oxidizer
- Immediately Dangerous to Life and Health (ILDH):
- Any condition that poses an immediate or delayed threat to life or that would cause irreversible adverse health effects.
Job Hazard Analysis:
A systematic approach to address hazards by looking at a task and focusing on the relationship between the laboratory worker, the task, the tools, and the work environment to identify the hazards and reduce the risks.
Risk Rating & Assessment
Risk Rating and Assessment rates risks using probability of occurrence and severity of consequences scales. This type of assessment should be incorporated early in the experimental process and requires a higher degree of user training.
Standard Operating Procedures (SOP):
A written series of steps that can be followed to correctly and safely obtain a desired outcome. In laboratories, SOP are typically developed for repetitive procedures which are known to have associated hazards where injury, property loss, or productivity loss could result if the steps were not followed precisely.
Structured What-if Analysis (SWIF):
A system-based risk identification technique that employs structured brainstorming, using predetermined guidewords and headings (for example, timing, amount, and so forth) in combination with prompts elicited from participants (which often begin with the phrases “What if…” or “How could…”), to examine risks and hazards at a systems or subsystems level.
What-if/HazOp:
A combination of What-if and HazOp techniques, deriving the benefits of both methods for a more comprehensive review.
What-if/HazOp/checklist:
A combination of What-if, HazOp, and checklist analysis techniques, deriving benefits from each methodology for a more comprehensive review.
Hazard Assessment templates are found below, including SOP, risk matrix, risk assessment for a chemical, and what-if analysis. The PI and lab may choose to use any method suitable for hazard assessment.