Efficient Plant December 2017 - 37

CHEMICAL
processing
SAFETY DATA SHEETS (SDS)
A Safety Data Sheet describes specific hazards
for a hazardous chemical to ensure proper
handling in the workplace. The manufacturer,
distributor, or importer of the chemical must
provide the sheet to users according to the Hazard Communication Standard (HCS), which was
revised in 2012, according to the U.S. Department of Labor's Occupational Safety and Health
Administration (OSHA), Washington.
The primary change in 2012 involved the
format of the Safety Data Sheets to create a
consistent layout that is easy to understand,
according to OSHA. The sheets contain 16
standard sections that break down the hazards

so that those who handle them understand the
potential risks.
The first eight sections cover basics of the
chemical, including the ingredients, handling
and storage, protection, and what to do in
case of exposure or an accident involving the
chemical, explains OSHA. Sections 9 through 11
describe the physical and chemical properties
and how the chemical behaves. Sections 12
through 15 appear on the sheet, but they are
not required to contain information. The final
section shows the preparation date or date the
document was updated.
OSHA requires that employers keep the

Safety Data Sheets for all chemicals used in
a location easily accessible to all employees.
The sheets must be in English and may also be
available in other languages.
Most Safety Data Sheets are available from
manufacturer websites, though you may have
to contact the manufacturer directly in some instances. There are several SDS search websites,
but a brief test of some indicates they may
be outdated, if they function at all. Some also
require registration.
Visit osha.gov/dsg/hazcom/index.html for
more details about the Hazard Communication
Standard.

connected to a reciprocating piston that pushes

of pump, wear can occur between the ball and

dosing pump after the diaphragm and/or check

and pulls it back and forth. In hydraulically actuat-

the seat in the check valve. "These days most

valves have been replaced to ensure the pump is

ed pumps, the reciprocating piston forces hydrau-

mechanically actuated pumps are dry and do not

operating within its parameters.

lic oil back and forth against the diaphragm to

contain any oil or grease internal to the pump for

cause the diaphragm to move. Both pump types

lubrication," he explained. "But if the pump does

use check valves mounted in the head to assist

have oil or grease, then it should be identiﬁed

in creating the pumping action.

and checked yearly."
Hydraulically actuated pumps that operate

MAINTENANCE
AND RELIABILITY
CHALLENGES
Holts said he cannot stress enough the impor-

BEST MAINTENANCE
PRACTICES

in continuous operation should be inspected

tance of converting from the run-it-until-it-breaks

quarterly to conﬁrm the hydraulic level is within

mentality to a focus on proactive maintenance.

Mechanically actuated pumps that operate in

the required volume, which is usually measured

"You buy a chemical metering pump because

continuous operation should be inspected yearly,

by an internal dipstick. It is recommended that

you want to accurately feed chemicals," he said.

which includes visually inspecting the diaphragm

the diaphragm also be checked and changed

"There are some wear components that will

for cracks, Holts said. It is a good policy to

annually for continuous-operating pumps,

continue to wear, and this will affect the accuracy

change the diaphragm every year for a pump that

especially in higher-pressure applications where

of the pump before the pump will fail. Ball check

is in continuous operation as wear and sepa-

hydraulically actuated diaphragms operate under

valves tend to lose seating action over a period

ration can occur between the PTFE face and

greater forces.

of time, but the pump still pumps so people don't

elastomer backing material. This is commonly
referred to as "delamination."

The suction and discharge check valves

think of proactively performing maintenance ev-

should also be inspected for signs of wear, espe-

ery one or two years. They think everything is still

cially between the ball and seats, Holts recom-

working. In reality, if they were to test the pumps

should also be inspected for signs of wear,

mends. "It is a good policy to change the suction

on a calibration column, they would see that they

especially between the ball and seats. It is a

and discharge check valves every year for a

are not pumping the volume they think they are

good policy to change the suction and dis-

pump in continuous operation. Depending on the

pumping because they are leaking internally

charge check valves every year for a pump in

liquid being pumped or the pump discharge pres-

around the check valves."

continuous operation.

sure or even the style of pump, wear can occur

The suction and discharge check valves

Depending on the liquid being pumped or
the pump discharge pressure or even the style

DECEMBER 2017

between the ball and the seat in the check valve."
It is good practice to recalibrate a metering or

New pumps being developed will automatically alarm the customer after 8,000 hours of
continuous operation or after two years of inter-

RELIABLE PUMPING SUPPLEMENT |

http://www.osha.gov/dsg/hazcom/index.html

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