Chemical Safety in the Workplace

Stewart Sampson Safety Services Nova Scotia

It can happen!! Hazard Communication MSDS Understanding Hazards Chemical Storage Personal Protective Equipment (PPE) Chemical Spill Response Waste Disposal General Safety Rules

Outline

Small tubes of petroleum ether were stored in an ordinary domestic freezer.

The tubes were not sealed well and the PE evaporated to a concentration exceeded the lower explosive limit, about 1.0%◦ Flash point of PE is -50 °C

A spark from an internal component of the freezer caused the PE to ignite

$500 000 in damage

What caused this?

It Can Happen!!

Anaerobic hood — an oxygen-free chamber used for working with bacteria that can't survive in oxygen

Lab personnel ignored a "warning system" designed to tell researchers when too much hydrogen enters the chamber and becomes flammable

An explosion resulted when the gas came into contact with an ignition source

Four people injured One critically

What caused this?

University of Missouri (2010)

Hazard Communication ◦ Allows workers to know the hazards and identities

of the chemicals they are exposed to while working. Describes measures they can take to protect themselves.

Hazards are communicated by:◦ Labels◦ Material Safety Data Sheets (MSDS)◦ Education and Training

Hazard Communication

MSDS – a document prepared by the chemical manufacturer that describes the:◦ physical and chemical properties◦ physical and health hazards◦ routes of exposure◦ precautions for safe handling and use◦ emergency and first-aid procedures◦ control measures

Material Safety Data Sheet (MSDS)

Pop Quiz

Flammable and Combustible Material

Poisonous and Infectious Material

Compressed Gas

Oxidizing Material

Corrosive Material

Dangerously Reactive Material

What are the WHMIS Hazard Classes?

Globally Harmonized System Classes

Toxicity◦ the ability of a chemical to cause harm◦ Like “Hazard” in general safety terms

Risk◦ likelihood a material will cause harm under the

conditions of use With proper handling, even highly toxic

chemicals can be used safely Less toxic chemicals can be extremely

hazardous if handled improperly

Toxicity and Risk

Inhalation – breathing (e.g., powders, fumes) Absorption – skin or mucus membranes Ingestion – entry through mouth Injection – through skin by foreign body

Acute Exposure (short term): eye irritation, nausea, dizziness, skin rash, burns, headache

Chronic Exposure (long term): long-term illness

Routes of Chemical Exposure

In 2008, Sangji was working with a bottle of t-butyl lithium dissolved in pentane

While using a syringe to withdraw a quantity of the reagent, it seems she accidentally pulled the plunger all the way out, introducing air and creating a flash fire◦ “Sangji was not familiar enough with the material and

delivery means to be doing the experiment on her own” Sangji was wearing nitrile gloves, safety glasses rather

than goggles, and a synthetic sweater with no lab coat When the fire ignited the gloves and the sweater, she

sustained second and third degree burns over 40 per cent of her body and was immediately hospitalized

She died 19 days later

Sheharbano Sangji - UCLA

eliminate the hazard;◦ Not using high shelves

substitute other materials, processes, or equipment;◦ Toluene for benzene

engineering controls; ◦ Fume hoods, engineered sharps◦ Eye Wash

Eye wash station; Disposable Eye Wash systems that increase awareness of potential hazards; administrative controls

◦ training and procedures, instructions, scheduling; Personal protective equipment

◦ Gloves, lab coats/uniforms, eye protection, safety shoes, respirators, face shields

◦ Gloves Use proper size Use proper glove material

Protection MeasuresHierarchy of risk controls

Glove Selection

Simpler Chart

Professor of chemistry at Dartmouth College specialized in toxic metal exposure

A few drops of dimethylmercury was accidentally spilled onto her hands◦ Protected only by latex glove◦ Tests later showed that DMM can rapidly permeate latex

gloves and enter the skin within 15 seconds Single exposure to DMM had raised her blood

mercury level to 80 times the toxic threshold◦ Delayed neurotoxic effects caused her to be hospitalized

after 5 months, and she died 10 months after the accident She was 48

Karen E. Wetterhahn

Chemical Storage

White = OKRed = Incompatible

Do not respond beyond your training level! Stop, think – Is this a Major spill?

◦ No Remove contaminated clothing Use proper PPE Contain spill Notify workers in your area Seek MSDS for advice Notify supervisor / security

◦ Yes Rescue Avoid the chemical Find the MSDS Telephone for help

Chemical Spill Response

Stop, think – Can I extinguish this fire?◦ Yes

Extinguish open flames Turn off gas / electricity Notify workers in your area Ventilate work area Notify supervisor / security

◦ No Evacuate area immediately and pull alarm Call emergency number

Chemical Fire

Minimize waste in the first place Do not pour chemical waste down the drain Know your chemical classification Use flame resistant container with label Don’t leave funnel on top of waste container Use proper mercury disposal (broken

thermometers) Call for pick up

Hazardous Waste

Store chemicals in their original containers Always wear appropriate safety gear and

work in a controlled environment Always dispose of chemicals properly Use care in handling contaminated

glassware or needles Always dispose of chemicals properly

General Safety Rules

Don’t buy chemicals you do not need Don’t eat, drink, smoke, chew gum or apply

cosmetics near chemicals Don’t mouth pipette Don’t use unlabeled containers Know chemical properties as well as toxicity

General Safety Rules

Any final questions? Thoughts?

Questions???