mr bakini mohd nor - sbmn synergy

OH&ES TRAINING CENTREOH&ES TRAINING CENTREOH&ES TRAINING CENTREOH&ES TRAINING CENTRE

SBMN SYNERGY SDN BHD(PSMB Training Provider Reg. No #1191)

7426, JALAN KUBANG KURUS, 24000 CUKAI, KEMAMAN,

TERENGGANU.

TEL : 09-8502490 / 91, 8597081

FAX : 09-8595324 / 8596819

EMAIL : [email protected]

[email protected]

SBMN SYNERGY SDN BHD

BAKINI MHD NOR MIM-CPT

3M COMPETENT TRAINER SINCE 1997

TRAINER ID # 01

RESPIRATORY PROTECTION PROGRAM TRAINED BY:

- 3M MALAYSIA SDN BHD

- 3M OH&ES DIVISION, USA

- COEH UNIVERSITY OF CALIFORNIA AT BERKELEY, USA

- AMERICAN INDUSTRIAL HYGIENE ASSOCIATION (AIHA), USA- AMERICAN INDUSTRIAL HYGIENE ASSOCIATION (AIHA), USA

- MALAYSIAN INDUSTRIAL HYGIENE ASSOCIATION (MIHA)

PROFESSIONAL MEMBERSHIPS:

- MEMBER OF NIOSH MALAYSIA

- FULL MEMBER OF MALAYSIAN INDUSTRIAL HYGIENE

ASSOCIATION (MIHA)

- INTERNATIONAL SOCIETY FOR RESPIRATORY PROTECTION (ISRP),

AMERICAS SECTION

- MEMBER OF AMERICAN CONFERENCE OF GOVERNMENTAL

INDUSTRIAL HYGIENISTS (ACGIH)

- AMERICAN INDUSTRIAL HYGIENE ASSOCIATION (AIHA), USA

DETERMINING COMPLIANCE WITH PERMISSIBIE DETERMINING COMPLIANCE WITH PERMISSIBIE

EXPOSURE LIMIT USING RESPIRATOR FOR NORMAL EXPOSURE LIMIT USING RESPIRATOR FOR NORMAL

WORKSHIFT AND EXTENDED WORKSHIFTWORKSHIFT AND EXTENDED WORKSHIFT

Objectives:

� Ensure worker’s exposure to any substance is kept as low as reasonably

practicable and does not exceed the substance's PEL.practicable and does not exceed the substance's PEL.

� Determine the daily time-weighted exposure during the period when the

respirator is worn and not worn.

� Taking into account the Assigned Protection Factor (APF) – the main

determinant factor that decides which respirator to be selected and Total Inward

Facial Leakage (TIL), when calculating the daily time-weighted exposure during

the period when the respirator is worn and not worn.

� Apply the Brief and Scala Model - most conservative estimate, when

adjusting the Permissible Exposure Limit (PEL) for working with extended workshift.

Daily time-weighted exposure =

for periods during respirator

is worn and not worn (dose)

is based on fundamental principles prescribed by :-

Compliance with permissible exposure limit using respirator

(Cw tw + Cnwtnw + Cniltnw )

8-hour

DETERMINING COMPLIANCE WITH PERMISSIBIE EXPOSURE DETERMINING COMPLIANCE WITH PERMISSIBIE EXPOSURE

LIMIT USING RESPIRATOR FOR NORMAL WORKSHIFT LIMIT USING RESPIRATOR FOR NORMAL WORKSHIFT


USECHH Regulations 2000: Regulation 8

(1) For the purpose of determining whether the employer has complied within

the permissible exposure limit, the degree of protection afforded by the

respirator for the periods during which the respirator is worn shall be taken

into account

(2) The period referred to in subregulation (1) shall be averaged with the

exposure level of the airborne concentration during the period when

respirators are not worn to determine the employee’s daily time-weighted

average exposure.


By applying the formula :



is worn and not worn (Dose)


8-hour

DETERMINING COMPLIANCE WITH PERMISSIBIE EXPOSURE LIMIT DETERMINING COMPLIANCE WITH PERMISSIBIE EXPOSURE LIMIT

USING RESPIRATOR FOR NORMAL WORKSHIFT USING RESPIRATOR FOR NORMAL WORKSHIFT


Where Cw tw = exposure concentration, duration while wearing respirator

Cnwtnw = exposure concentration, duration while not wearing respirator

Cniltnw = no exposure concentration or zero exposure

TWA = C1T1 + C2T2 + EE..+ CnTn(Dose)

Total Time ( 8-hour)


8-hour

is based on


Example

Exposure : 350 ppm of Xylene

for 8-hr period

Don / Wear : Half facepiece respirator




Type: Air Purifying Respirator (APR)

Note : (APF = 10, Total Inward Facial Leakage : 10%)

a. Time duration doning/ wearing 5 hours

3M 6000 series half facepiece respirator

b. Time duration not doning/ wearing 1 hour


c. Time duration not doning/ wearing 2 hours


when do not expose to xylene (Lunch ,safety briefing and prayers time)



Daily time-weighted exposure = (Cw tw + Cnwtnw + Cniltnw )






Step 1 :-

Cw tw = exposure concentration, duration while wearing respirator

= 35 ppm x 5 hours

= 175 ppm


8-hour


Explaination:

Inhalation of exposure = Total Inward Facial Leakage x Exposure

for Xylene when respirator = 10% x 350 ppm

Is worn = 35 ppm of Xylene




Types of RespiratorTotal Inward

Facial

Leakage

APF = Co

Ci

= 100%

10%

Half Facepiece (Air

Purifying Respirator)

10% 10

Note:-

Total Inward Facial Leakage of 10% is the maximum leakage for a given type of

respirator allowed by NIOSH,USA. APF is also known as Degree of Protection.

USECHH Regulations 2000: Regulation 8 states that:

(3) For the purpose of this regulation, “degree of protection” means the ratio

of the airborne concentration of the contaminant outside the respirator to the

concentration of the contaminant inside the facepiece of the respirator.

Airborne Concentration of the Workplace Exposure



Airborne Concentration of the

Contaminants Outside the Respirator

= =

Concentration of the Contaminant

Inside the Respirator Facepiece

Degree of

Protection

Degree of Protection = Assigned Protection Factor ( APF )

Total Inward

Leakage (TIL) or

Exposure Limit

=

Workplace Exposure

Concentration

“The effectiveness (degree of protection) of a respirator determined by its protection factor

(PR). In the selection of respirators, the assigned protection factors are used.”

- “Guidelines on the use of Personal Protective Equipment Against

Chemicals Hazards” 2005. ( )

*Workplace Exposure Concentration

Total Inward Leakage (TIL) or

Exposure Limit

APF needed =

ASSIGNED PROTECTION FACTOR (APF)ASSIGNED PROTECTION FACTOR (APF)

By adopting the Right APF, the leakage or Total Inward Leakage

(TIL) can be reduced below the Exposure Limit

* “Employers must identify and evaluate the respiratory hazard(s) in the workplace. This

evaluation must include a reasonable estimate of employee exposures to respiratory

hazard (s) and an identification of the contaminant’s chemical state and physical form”

- “Guidelines On the Use of Personal Protective Equipment Against

Chemicals Hazards” 2005. (Page 24)

* 8-hr TWA or exposure within 15-minute TWA

Step 2 :-



without wearing respirator (100% exposure)



= (350 ppm x 1 hour)

= 350 ppm

Step 3 :-

Cniltnw = rest period without exposure and not wearing respirator

= zero exposure x 2 hours

= 0 ppm

Step 4 :-

Total (Cw tw + Cnwtnw + Cniltnw ) divide by 8-hour (duration of exposure)

= 175 ppm + 350 ppm + 0 ppm

8-hour



8-hour

= 66 ppm of Xylene (Dose)

66 ppm of Xylene is below the PEL of Xylene which is

100 ppm. This is in compliance with the PEL Limits Using

Respirators USECHH Regulations 2000 : Regulation 8.

Able to avoid occupational diseases.

The validity of this calculation for the daily time-weighted exposure

will be based on the following considerations :-

1. The Respiratory Protective Equipment (RPE) must be approved by Director

General of DOSH and tested according to international recognized standards

such as ANSI, NIOSH (USA), AS,NZS, JIS and others.

2. Respirator selected must be based on

Assigned Protection Factor (APF) > Hazard Ratio

for the selected respirator Exposure 8-hr TWA

PEL

Continued(..

[ ]

*Workplace Exposure Concentration

Total Inward Leakage (TIL)

APF needed =Total Inward Leakage (TIL)

By adopting the Right APF, the leakage or Total Inward Leakage

(TIL) can be reduced below the Exposure Limit

* “Employers must identify and evaluate the respiratory hazard(s) in the workplace. This

evaluation must include a reasonable estimate of employee exposures to respiratory

hazard (s) and an identification of the contaminant’s chemical state and physical form”

- “Guidelines On the Use of Personal Protective Equipment Against

Chemicals Hazards” 2005. (Page 24)

* 8-hr TWA or exposure within 15-minute TWA

3. Respirator facepiece and equipment must be free from defects to avoid

malfunction of the respirator.

Continued(..

4. Correct selection of filtering media for negative air purifiying respirator.

Continued(..

Beware!!!

The use of incorrect cartridge or

incorrect filtering gives workers a false

sense of security and in addition may

cause occupational diseases.

5. Respirator user must passed the Qualitative Fit-Test or Quantitative Fit-Test

conducted by competent person trained by respirator manufacturer. Respirator

Fit Test must be conducted at least once a year recommended by most

respirator manufacturers.

Continued(..

6. Respirator User Seal Check (Fit Check) must be performed after donning the

respirator facepiece.

Continued(..

The main objective of User Seal Check is to ensure proper fitting of tight fitting

facepiece and minimize respirator faceseal leakages.

7. Prior doning, ensure that respirator user must be free from facial hair such as

stubble, moustache, beard, and long side burns, that might affect the sealing

surface of the respirator. Respirator user must also ensure that other PPE such

as Goggle, Safety Spectacles , or other PPE should not interfere with the face-

to-facepiece seal or valve function.

Continued(..

8. Appropriate chemical protective clothing including glove and other relevant PPE

must be don when chemical can be absorbed through skin.

Continued(..

Chemical

Resistant glove

Chemical Protective

Clothing

Chemical

Resistant Boot

Respirator

9. RPE must be thoroughly clean, kept store so that contaminated it free from

chemical contamination.

Continued(..


Example






USING RESPIRATOR FOR EXTENDED WORKSHIFTUSING RESPIRATOR FOR EXTENDED WORKSHIFT


No. of hours worked : 12 hours per shift







when do not expose to Xylene (Lunch ,safety briefing and prayers time)









Step 1 :-


= 35 ppm x 9 hours

= 315 ppm


12-hour


Explaination:








Facial

Leakage

APF = Co

Ci

= 100%

10%

Half Facepiece (Air


10% 10

Note:-

Total Inward Facial Leakage of 10% is the maximum leakage for a given type of

respirator allowed by NIOSH,USA. APF is also known as Degree of Protection.

Step 2 :-



without wearing respirator (100% exposure)




= 350 ppm

Step 3 :-



= 0 ppm

Step 4 :-


= 315 ppm + 350 ppm + 0 ppm

12-hour


USING RESPIRATOR FOR EXTENDED WORKSHIFT USING RESPIRATOR FOR EXTENDED WORKSHIFT

12-hour


The normal PEL for Xylene 100 ppm is no longer valid for

extended workshift. Need to be adjusted using Brief and Scala

model.

Selected Model : Brief and Scala

Brief and Scala model is the simplest and most

conservative model. “Conservative” means results in the



conservative model. “Conservative” means results in the

greatest reduction of the exposure limit.

Brief and Scala compensates for unusual work

schedules by reducing the permissible concentration in

proportion to both the increase in exposure time and the

reduction in recovery time.

BRIEF AND SCALA MODEL

This model, originally derived within the petroleum industry, reduces the 8-hour

OEL/PEL proportionally for both increased exposure and reduced recovery time.

The suggested approach is set out below.

Daily Adjustments of Occupational Exposure Limits :



Daily Adjustments of Occupational Exposure Limits :

Daily Reduction Factor = { ( )}

Where h = hours worked per day

Adjusted Exposure Limit = 8 hr TLV/PEL/OEL x Daily Reduction Factor

{ ( )}

8 x

h

24 – h

16

8

h24 – h

16

ADJUSTMENT OF TLV/PEL/OEL FOR EXTENDED WORKSHIFT

USING BRIEF AND SCALA MODEL

EXTENDED WORKSHIFT

Work Duration ( h )

(Hours Worked Per Day)

Daily Reduction Factor

10 hours 0.7

12 hours 0.512 hours 0.5

Adjusted PEL = PEL x Daily Reduction Factor

Explaination on Derivation of Reduction Factor

A) Extended workshift = 10 hours worked per day

Reduction Factor = (8/10) x (24 – 10) / 16)

= 0.7 (Reduction Factor)

B) Extended Workshift = 12 hours worked per day

Reduction Factor = (8/12) x (24 – 12) / 16)

= 0.5 (Reduction Factor)

ADJUSTMENT OF TLV/PEL/OEL FOR EXTENDED WORKSHIFT

USING BRIEF AND SCALA MODEL

Work Duration ( h )10 hours 12 hours

Chemical Exposed : Xylene

TLV / PEL / OEL : 100 ppm

Formula for Brief & Scala : 8 x (24-h) x PEL

16 x h

Work Duration ( h )

(Hours Worked Per Day)10 hours 12 hours

Rest Period

(Recovery Time)14 hours 12 hours

Daily Reduction Factor 0.7 0.5

Adjusted TLV/PEL/OEL

( ppm )70 ppm 50 ppm

Note :-

•↑Work Duration ↓ Recovery Time ↓ Adjusted TLV/PEL/OEL

•Brief and Scala Model is the most conservative estimate.

BRIEF AND SCALA MODEL

Adjusted Exposure Limit = 8 x (24 – h) x PEL

for Xylene for 12 hours 16 x h



for Xylene for 12 hours 16 x h

exposure

= 8 x (24 – 12) x 100 ppm

16 x 12

= 50 ppm

where h = hours worked per day

55 ppm is the Daily Time-Weighted > 50 ppm adjust PEL for Xylene using

Average for 12 hours exposure Brief & Scale Model for 12 hours work

period.



When Daily TWA for 12-hr exposure exceeded the adjusted PEL, Xylene may

be elevated in the blood which may lead to occupational disease.

Recommendations :-

First recommendation

Select respirator with next higher APF which Full Facepiece (APR) with APF of 50.

APF = *50

* Assigned Protection Factors for the Revised Respiratory

Protection Standard ; Occupational Safety and Health

Administration U.S. Department of Labor ; OSHA 3352-02,

2009


Example


for 12-hr period

Don / Wear : Full facepiece respirator






No. of hours worked : 12 hours per shift







when do not expose to xylene (Lunch ,safety briefing and prayers time)









Step 1 :-


= 7 ppm x 9 hours

= 63 ppm


12-hour


Explaination:







Facial Leakage

APF = Co

Ci

= 100%

2%

Half Facepiece (Air


2% *50

Note:-

Total Inward Facial Leakage of 2% is the maximum leakage for a given type of respirator

allowed by NIOSH,USA. APF is also known as Degree of Protection.

* Assigned Protection Factors for the Revised Respiratory Protection Standard ; Occupational Safety and

Health Administration U.S. Department of Labor ; OSHA 3352-02, 2009

Step 2 :-


Exposure without wearing respirator (100% exposure)

: 350 ppm of Xylene




= 350 ppm

Step 3 :-



= 0 ppm

Step 4 :-


= 63 ppm + 350 ppm + 0 ppm

12-hour



12-hour


The normal PEL for Xylene 100 ppm is no longer valid for

extended workshift.

34 ppm is the Daily Time-Weighted < 50 ppm adjusted PEL for Xylene using

Average 12 hours exposure Brief & Scala Model for 12 hours

using Full Facepiece (APR) work period.



Occupational Disease can be avoided.Occupational Disease can be avoided.

Second recommendation:

Half Facepiece APF can be selected provided the duration of exposure is

reduced. Implement job rotation

LIMITATIONS ON BRIEF AND SCALE MODEL

� Not applicable to justify very high exposures for short

durations



durations

� Not appropriate for many of the metals and mineral

dust.

However, recommended standards for extended

workshift operation, please refer to :-

“Recommended Exposure Reduction Factors for

Western Australian Mining Industry”.

Reference :-

Department of Minerals and

Energy Western

Australia, Discussion Paper

: Unusual Workshift and

Occupational Exposure

Standards. J

Oostehorf, 1983. Document

No. ZME263AA.

LIMITATIONS ON BRIEF AND SCALE MODEL

Example

Exposure to silica dust for extended workshift for 192 hours per month.

Health effect of silica is Silicosis. Typical respiratory disease. Threshold

Limit Value for Silica is 0.025 mg/m3



Limit Value for Silica is 0.025 mg/m3

TLV Silica (R) Exposure Reduction Factor 170/x

TLV/BEI x for more than working hours

2011 ACGIH Booklet > 170 hours /month

0.025 mg/m3 x 170

[(R) means respirable] 192

= 0.022 mg/m3

Adjusted TLV for Silica Working hours = 0.022 mg/m3 of Silica

greater than 170 hours per month

Take Care and Good Luck

mr bakini mohd nor - sbmn synergy

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