Lab Safety

the volume in each flammable storage cabinet should not exceed

60 gallons

PEL

Permissible Exposure Limit

Most acid are considered corrosives substances

Physically, corrosives can disrupt cell membranes, coagulate proteins, and cause of death of essential cellular components

Toxic Lethal Dose

The lowest dose reported to have caused DEATH IN MAN, or as the lowest single killing dose reported for animals

Class IC:

a Flashpoints at or above 22.8 and below 37.8 these include ethyl acetate

Proper chemical storage of chemicals in the histology laboratory is

a not just a matter of safety ,but security

chemicals should be grouped and stored

according to compatible families of compounds

Flammable liquids requiring refrigeration must be place

in explosion proof refrigerators

Lab safety Audit

include 3 sections: Training Standard Operational Procedure SOP Disposal

Hazard Chemicals may enter the body via

inhalation,ingestion,or absorption

FLASH POINT

is the lowest temperature at which a flammable liquid gives off sufficient vapor to form an ignitable mixture with air.

OSHA identifies carcinogens as

materials that can cause cancer or other chronic conditions in humans materials that have shown to cause cancer in test animals

Hazcom

(Hazards Communication) became effective on May 20 1988

MSDS

(Material Safety data Sheet )is a fact sheet for chemicals that possess a physical or health hazard in he work place

Corrosive substances:

-Are defined as substances that can destroy mild steel under certain condition -As substances that will cause injury to the skin and eyes by direct contact -or will produce severe damage to the tissues of the respiratory and alimentary tracts when inhaled or ingested

Flammable chemicals (STORED)

-Should be stored in approved containers -no more than three cabinets should be located in each fire area

Class IB:

-a Flash point below 22.8 -a boiling point at or above 37.8 -These include acetone, ethyl ,and isopropyl alcohols, butanol, pyridine, toluene ,xylene and some xylene substitute

Class IA:

-a flashpoint below 22.8 degrees C -a Boiling point is below 37.8 degrees -these include ether, methanol, iso-pentane, and propylene oxide

Liquid chemicals (STORED)

-should be stored in secondary containment units -these are usually made out of strong plastic ad can prevent leaks or prevent bottles from breaking

Since we encounter so many different types of chemicals from carcinogens, to corrosives, to flammables, to irritants

-we need to know how to properly store these chemicals to avoid any mishaps -chemicals should be stored in appropriate containers and areas. -chemicals should be stored in shelves or cabinets, at or below eye level - NO chemical should be stored above you head -No be stored in fume hoods or on the floor -if using shelves these must have edges or lips to avoid sliding off of chemical bottles -Should be stored in original container because they should already be properly labeled from the manufacturing plant. -should be stored ONLY if you are going to use them in the immediate future.

the PEL for Formaldehyde is

.75ppm

the maximum working volume of flammable solvents allowed outside a storage cabinet is

10 gallon per room

PEL for Xylene is

100ppm; 435mg over an 8 hour period

SELT for Xylene is

150 ppm; 655 mg over 15 minute peiod

the STEL for formaldehyde is

2.0ppm over a 15-minute period

known carcinogens in histology lab;

Arsenic compounds such as cacodylate buffers Benzene Chromium oxide Formaldehyde Benzidine a dye Benzidine based dyes such as biebrich scarlet,congo red,oil red o,wood stain scarlet,Ponceau S, trypan blue, bordeaux

Examples of material that have shown high carcinogenic in test animal

Asbestos Benzene

In histology two of the most hazardous chemicals in constant use are

Formaldehyde and Xylene

corrosives substances CONSTANTLY USED IN HISTOLOGY

HCL NITRIC ACID ACETIC ACID MERCURIC CHLORIDE CHROMIC ACID ET AL-ETHANOL

examples of toxic chemicals:

Hydrocarbons: Xylene Toluene Formaldehyde Metallic compounds: Mercury,Chromium,silver Carcinogens: Formaldehyde Bis-chloromethyl ether pararosaniline

Flammable liquids are classified into 3 classes

IA,IB,IC

STEL

Maximum allowable TWA for any 15 minute period during an 8-hour work period

Classes of HAZARDS

Mechanical Biological or Infectious Chemical (Toxic, Corrosive, Explosive)

different type of gloves are used to handle working with chemicals

Natural rubber Neoprene Nitrile Vinyl

RSIs

Repetitive Strain Injuries (may cause carpal tunnel syndrome

STEL

Short-term Exposure Limit

Chemical Hazard SOP`S

Standard operational procedures for handling carcinogens applies to both solid and liquid mixtures cotaining more that 1.0% of regulated carcinogens Ensure all work in areas designated for work with carcinogens such as as under a hood Limit access to the restricted area, post signs indicating the potencial danger,such as CANCER-SUSPECT IN USE/AUTHORIZED PERSONNEL ONLY Always have some one else working in the area with you in case of emergency HOODS should be provide when ever cancer or toxic substances are to be used if there are no hood you must wear a respirator with an absolute filter N-100 Emergency contingency plans must be in place in case of accidents Medical attention must be arranged for anyone involved in the ingestion,inhalation or inoculation of one the chemicals

OSHA`s "Right to know" law or HAZCOM

States that you have the right to know what chemicals you are exposed to while doing job

NSH`S target Organ Poster has listed the following organs, as targets of chemical induced hazards

The liver,Kidney, nervous system, blood or bone marrow,lung,reproductive organs, skin and eyes

Toxic Dose Low

The lowest dose of a substance, that will produce a TOXIC EFFECT IN MAN , when introduced by ay route of entry

TWA

Time-weighted average

a small dose of exposure to a hazardous material over a long period of time can be

as harmful as a large dose over a short period time

Flammable liquids have a FLASH POINT

below 37.8 degrees Celsius or 100 degrees Fahrenheit

Do not store any chemical whose use will not be in the immediate future especially if it is a

flammable, volatile or explosive chemical

OSHA requires labels and MSDS designation

for regulated carcinogens

In 1993 OSHA

gave its final ruling on the Formaldehyde standard employers must monitor employees when they first enter a job and again if there is a change of personnel or procedure

STEL) (PEL) If any of these exceed the recommended amount of exposure level then

repeated testing is done and employee monitoring of the work practice is also done

Flammables

should be stored in approved flammable cabinets only must be kept away from heat and sparks also if they come in glass bottles, they should contain no more than 4 liters of liquid

LD 50

the lowest calculate dose expected to cause death of 50 % of an experimental animal population as determined by from exposure to a substance by any route other than inhalation

PEL

the maximum allowable 8 hour TWA of exposure to a substance as defied by OSHA

Accidental ingestion should not ocurre since

there should be no eating,drinking,smoking or mouth pipetting in lab

gloves should be worn at all times

to avoid absorption of hazardous chemicals via the skin

hood as well as adequate ventilation systems are used

to avoid inhalation of hazardous chemicals via the skin

we need to ensure that the proper glove is used

to avoid skin contaminatio