Lab safety

Laboratory risks

Module 5.1 - Learning objectives

  • Understand the difference between hazard and risk
  • Be familiar with project‑related responsibilities (e.g., project risk assessments)
  • Understand the routes of entry
  • Understand the requirement for constant vigilance

With hazard comes risk. A risk is the chance or probability that someone or something will be affected in a particular way. The effect is a deviation from the expected that may have positive, negative or neutral consequences. As an example, a container of hydrochloric acid (HCl) is a hazard. The risk is the container falling, splashing and causing a chemical burn. For laboratories that require HCl as part of their operational processes, they will focus on risk control or mitigation measures to reduce their exposure. Risk is inherent to laboratory spaces, and users must be ready with appropriate mitigation measures, even for situations with which they are familiar and regularly encounter.

Module 5.2 - Lab risk assessments

Risk can be quantified using the equation Risk = Frequency x Severity and be plotted by risk rating – that is, assigning values to the probability and the severity, typically on a scale of 1 (least likely/severe) to 5 (most likely/severe). All research projects must be evaluated to ensure that reasonably foreseeable hazards have been identified, risks are mitigated to the extent reasonable and corrective action (where necessary) is implemented. The University has developed tools to assist supervisors in evaluating their projects, mainly through the use of project risk assessments (PDF, 531KB). Before doing work:

Plan

  • What is the scope of the project?
  • Who is responsible for what?
  • What legal requirements exist?
  • How will the work be done?
  • What are the hazards associated with the project? What are the risks?

Do

  • Assign competent personnel to the project.
  • Implement controls.
  • Conduct the project.
  • Document and maintain records.

Check

  • Are things progressing as anticipated? How do you know?

Act

  • Are adjustments or modifications required? Is corrective action needed?

Completed risk assessments can be reviewed by the health, safety and risk manager and/or the Office of the Chief Risk Officer. The purpose of the review is to offer a second set of eyes from a hazard and risk mitigation perspective. Supervisors and principal investigators maintain responsibility for ensuring that work is planned and executed safely.

Module 5.3 - Routes of entry

With any hazardous substance, there is a way for it to cause harm. Illnesses are the result of exposures entering the body through one (or more) of the four main routes of entry:

  • Inhalation (breathing) – most common route of entry
  • Absorption (skin contact, entry through mucous membranes) – possible result of spills, open abrasions, etc.
  • Ingestion (swallowing, eating) – less likely in a laboratory that does not permit eating or drinking
  • Injection (introduction directly into the body) – can possibly occur when working with sharp materials or syringes

No matter how a hazardous material enters the body, it circulates within and targets vulnerable areas. Certain materials have specific organ toxicity that can accumulate with frequent, prolonged exposure. Certain substances require additional means of assessment and protection, namely, those classified as designated substances, including arsenic, benzene, lead and mercury. These materials require operational use assessments to evaluate if the health of a person can be affected. A process for assessing these specific substances is included as part of the Designated Substances Program (PDF, 1.5MB) and must be completed where they are present and/or used.

Module 5.4 - Vigilance

Laboratory spaces require constant monitoring and vigilance of workplace parties to ensure that foreseeable hazards and risks are anticipated and controlled. This may be accomplished through any number of means; however, it all must be coordinated and funnelled through the local supervisor in order to implement corrective actions, as necessary. Examples include:

  • Formalizing operating procedures – a well-developed, clearly communicated operational procedure will set expectations of what needs to be done and how it is expected to be accomplished. It is like a recipe for a cake – if you follow the recipe, you will get a delicious cake. Too much deviation from the recipe results in a cake that you would not be able to feed to a raccoon.
  • Inspections – periodic and regular inspections identify situations that need corrective action. Inspections may be specifically focused or general in nature. Examples include inspections of:
    • Fire extinguishers (that they are accessible, fully charged, in their proper locations, etc.)
    • Emergency buttons (that they work as intended)
    • Eyewashes (that they work as intended)
    • Chemical storage (that chemicals are in secondary containers, that the storage cabinet has proper airflow if vented, that cabinet doors close, etc.)
    • Tubing for water, vacuum or gas applications (that lines are secure, there are no leaks, etc.)
    • Glassware (that there are no cracks, microfractures, stars, chips, etc.)
  • Job observation – regularly observing how work is done reinforces good work practices and allows for early intervention, as necessary.

Vigilance is not just for individuals; it is also about the physical security of the laboratory and the material it contains. The physical security of the lab space is the responsibility of all workplace parties. However, the supervisor is responsible for their lab space and the people permitted to work there. Physical security is established through:

  • Doors, locks, keys, card access and biometric scans

Doors must be kept closed to preserve security as well as to maintain proper balance of the ventilation system. No keys or access fobs/cards may be shared, nor is providing access to unauthorized personnel permissible.

  • Alarms and cameras

Codes for alarms are not to be shared with unauthorized personnel. Cameras are strategically placed for the protection of the University community.

  • Security assessment

Certain materials require pre-use security assessments, due to their identification as part of import/export control lists or as controlled goods. The Office of the Chief Risk Officer will help you to determine if a security assessment is needed and will perform the necessary steps to complete that registration on your behalf. Contact the Office of the Chief Risk Officer well in advance of any required access or planned research using controlled goods.

These control measures are not to be defeated or unlawfully bypassed, as they have been implemented for the protection of everyone as well as the institution.

Module 5.5 - Lab equipment

Lab equipment intended for use to accomplish basic tasks can also pose hazards to users.

  • fume hood is a mechanically ventilated, partially enclosed workspace in which harmful materials can be handled more safely. The primary function of a fume hood is to capture, contain and exhaust gases, vapours and aerosols generated within the fume hood enclosure, thereby helping to protect the user. Users access the interior of the fume hood through a vertical and/or horizontal sash, which also serves as a physical barrier between the work area and the user. Fume hoods are used in various workplaces, including the University’s teaching and research labs. Sashes should be positioned as low as possible to provide physical protection as well as to maintain suitable face velocity. Fume hood functionality can be verified through the face velocity monitor on the side of the hood (typically 80–100 feet per minute for standard hoods) or by using Kimwipes or tissues at the sash opening. The tissue should be drawn slightly into the fume hood cabinet.

  • An autoclave is a pressure vessel that uses elevated temperatures and pressures to decontaminate and/or sterilize. Given the conditions in which this equipment operates, it is vital that users fully understand autoclave operating principles and safety features. The University of Ottawa offers regular Autoclave Safety training, which must be taken by all those who operate autoclaves or generate materials that someone else will autoclave. A key component of this training is to understand which materials must never be placed in an autoclave, e.g., chlorinated compounds.
  • centrifuge is a motor‐driven instrument that spins liquid sample vials at high speed to separate fluids of greater and lesser density. Centrifuges come in different sizes and sample numbers. Centrifuges must remain carefully balanced due to their high operating speeds; even a slight imbalance at rest can cause significantly unbalanced forces during operation, which can lead to injury and property damage. Because centrifuges generate tremendous forces, they must be interlocked, meaning that the device cannot start or operate with the lid open or removed. Always inspect the centrifuge before operating, log its use in the central centrifuge logbook, and maintain it according to manufacturer specifications. Another hazard associated with the centrifuge’s high speeds is the potential aerosolization of hazardous materials. Special aerosol‐tight gaskets are available to use when running a centrifuge at high speeds with hazardous materials. Your supervisor will provide further safe‐use procedures.
  • cryostat is used to cut histological slides to micrometre precision, with tissues sectioned as thin as one micrometre. Specimens are mounted in a climate‐controlled cabinet with a typical temperature ranging between ‐20°C and ‐30°C. The slide is placed inside the cryostat and advanced toward the sharp blade inside. This allows tissues to be sectioned and mounted on slides for use elsewhere. The mounted slide is removed from the cryostat and dried. The most common hazard with cryostats is contact with the sharp blade of the instrument, which can cause lacerations. Therefore, when changing the cryostat blade or performing routine maintenance (i.e., cleaning the equipment), use cut‐resistant gloves and/or lock the blade rotation and use tongs or forceps to maintain distance when removing the slide. Your supervisor will provide further safe‐use procedures.
  • Vacuum pumps need regular maintenance, including drive belt replacement. Always ensure that the drive belt guard is reinstalled once the belt is replaced to prevent physical injury.
  • Oil baths are used to heat reaction vessels to pre‑set temperatures. This is typically controlled with a thermocouple, a digital thermometer that monitors the temperature and controls how hot the hot plate gets via a feedback loop. Always ensure that the thermocouple is securely held in place, or else it will no longer read the temperature of the hot plate and will uncontrollably heat the oil bath until it reaches its flash point.
    • Be aware of the upper temperature limit of the hot bath being used. Oil has a flash point temperature that, when exceeded, has a high risk of combusting or catching fire.
    • Mineral oil: 160oC
    • Silicone oil: >300oC
    • If higher temperatures are required, use a solid medium such as sand or iron/aluminum pellets.

Heating mantles are devices used to heat round‑bottom flasks using electrical filaments. They are designed to be hooked into a Variac (variable A/C) so that the device receives less than 120 volts. Most heating mantles operate below 110 volts. If left too long at a higher voltage or accidentally plugged directly into an outlet, they will overheat and catch fire.