General Lab Safety

ece445Spring 2013

Dane Sievers

Why a lecture on safety?

Engineers make things.

To make things, engineers use tools, chemicals, and electricity.

Tools, chemicals, and electricity can hurt.

Getting hurt, well… hurts! (And dying is even worse)

Hurt (or dead) engineers can’t make things.

Or kill.

And…

Why a lecture on safety?

These things engineers make are used by people.

These things can hurt people.

Or kill people.

Hurting (or killing) people is bad.

Even worse than bad.

So…

Why a lecture on safety?

Safety must be engineered into

the making and use of things.

Safety in Practice

Ummm… I hate to say

it…It’s so clichéd…

But I have to say it…

Safety is No Accident!

Safety in Practice

In order to be safe, you must know the dangers present.

To know the dangers means you must learn about the equipment, chemicals, and technology you will be using.

Learning means you must study.

To study means you must read.

Safety in Practice - LIST

Before beginning work on your chosen project, identify and list:

Equipment needed

– Tools

– Chemicals

– Electrical components

– Fabrication techniques

Safety in Practice – COMPILEFrom this list find and compile the appropriate documentation.

– User manuals

– Data sheets

– MSDSs

– Accepted SOPs (standard operating procedures)Put these documents into a folder or binder

for future reference.

Label your folder/binder “SAFETY MANUAL”.

Pretty clever name, huh?

Safety in Practice – READ

A folder full of documents is of no value unless you read them.

SO READ THEM!

Safety in Practice – IDENTIFYAs you read through the documents, identify the hazards associated with use of the product.Create a brief ‘cheat sheet’ list of the hazards and put it in the front of your SAFETY MANUAL.

Safety in Practice – PLAN

For each hazard found, prepare a plan to control the hazard.

Control measures may include (but not limited to):

– Proper PPEs (personal protective equipment) required

– Containment (fume hoods, fume extractors, respirators)

– Proper safety guards/physical barriers

– Other engineering controls needed to minimize hazards

Put this plan into the SAFETY MANUAL.

Safety in Practice – THINK

Now is the time to review the information in your SAFETY MANUAL.

‘Why?’ you ask?

Everyone say “Tell us about Emil!”

Note: Audience participation required on next item…

Safety in Practice – IMPLEMENTNow that you have a document covering the safety aspects of your project…

PUT IT TO USE!This exercise wasn’t designed to just take up your time. It was designed so that you, others around you, and the end user will survive your project without getting hurt!

Resources

If you are unsure about something you are doing, don’t do it!

Just ask…– TA– Professor– Lab engineer– Electronics Shop– Safety Professionals on campus

• DRS (Division of Research Safety) – www.drs.illinois.edu

Safety – Electricity and PeopleDepartment Policy Highlights

– Undergraduate students must work at least in pairs in our labs.

– When full ac wall potential is in use, a faculty member or TA must be present. At least two people must be present.

– No food or drink at lab benches.

Safety – Electricity and PeopleIf a problem occurs or is suspected

– Shut off power

– If an accident or emergency occurs, dial 911

– Locate the trouble and fix before restoring power

– The Electronics Shop can help if necessary • 265 EL

• 333-2173

Safety – Electricity and PeoplePersonnel Safety Issues

– Shock hazards exist in the labs

– Most common problems are from • Spilled Drinks

• Careless wiring

– Loose clothing, neckties, and jewelry are dangerous when working with rotating machinery

– Burns: it only takes a watt to make small parts hot

Safety – Electricity and PeopleEffects of electrical shock (60 Hz ac, 1s duration

Extracted from http://www.osha.gov/SLTC/etools/construction/electrical_incidents/eleccurrent.html Current Level Probable Effect

1 mA Perception level. Slight tingling sensation. Still dangerous under certain conditions.

5 mA Slight shock felt; not painful but disturbing. Average individual can let go. However, strong involuntary reactions to shocks in this range may lead to injuries.

6mA - 16mA Painful shock, begin to lose muscular control. Commonly referred to as the freezing current or "let-go" range.

17mA - 99mA Extreme pain, respiratory arrest, severe muscular contractions. Individual cannot let go. Death is possible.

100mA - 2000mA Ventricular fibrillation (uneven, uncoordinated pumping of the heart.) Muscular contraction and nerve damage begins to occur. Death is likely.

> 2,000mA Cardiac arrest, internal organ damage, and severe burns. Death is probable.

Safety – Electricity and PeopleSome good advice:

– Turn power off when changing circuits• While working on a circuit use the ‘one-hand’ rule –

keep one hand in pocket or behind back to minimize risk of shock across the heart

– Keep a tight, neat setup• Safer than the “rat’s nest” technique

• Easier to debug and usually works better!

– When in doubt, shut off the power

– If it doesn’t work, it probably isn’t the instrument…

Safety – Electricity and Instruments

Equipment damage is one of the biggest safety issues.

Potential Issues– Grounding

• Grounded probes (oscilloscopes)

• Sources

– Ratings• Do instrument ratings match the signal?

Safety – Chemicals

Electrical engineers are not chemists – but they do use chemicals.

Chemicals commonly used include– Solder

– Flux and flux remover

– Solvents

– PCB substrates

Safety – Chemicals

The most important rules when using chemicals:

– Do not put chemical waste in the trash– Do not pour chemical waste down the sink– No food or drink in a lab with chemicals.– Read the MSDS for a chemical before using– Label containers– Transport chemicals safely– Keep incompatibles apart

– acids/bases– flammables/oxidizers

Safety – Chemicals

Personal Protective Equipment– Use appropriate PPEs when handling chemicals

PPEs may include:– Safety glasses/goggles (if potential for splashing liquids)

– Appropriate gloves (compatible with chemical(s) used)

– Respirators (for fumes/vapors)

– Protective clothing (apron, lab coats, coveralls)

Safety – Chemicals

Engineering Controls“The basic concept behind engineering controls is that, to the extent feasible, the work environment and the job itself should be designed to eliminate hazards or reduce exposure to hazards.” (OSHA)

Engineering Controls may include:– Fume hoods (when dangerous vapors could be released)

– Fume extractors (e.g. extract solder fumes)

Safety – Chemicals

Chemical SpillsIf a chemical is spilled and you don’t know how to clean it up safely, call

911

Safety – Wrap Up

When it comes to safety:

If you are unsure, don’t do it!